A doctor who recently returned from Guinea has tested positive for Ebola - the first case of the deadly virus in New York City.
Here is a timeline of Craig Spencer's movements since he got back from the West African nation:
When did he return from Guinea?
Spencer came back to the United States last week after treating Ebola patients in Guinea, where he worked for Doctors Without Borders.
He completed his work in Guinea on October 12 and left the country two days later via Brussels.
He arrived at John F. Kennedy International Airport on October 17, but he exhibited no symptoms of the virus until Thursday morning, said Dr. Mary Travis Bassett, New York City's health commissioner.
The physician, who works at Columbia Presbyterian Hospital, was checking his temperature twice a day. He has not seen any patients since his return.
Did he have any symptoms?
The 33-year-old did not have any symptoms after his return, but developed a fever, nausea, pain and fatigue Thursday morning. He began feeling sluggish a couple of days ago, and his fever spiked to 100.3 degrees Thursday, authorities said.
How many people has he been in contact with?
Spencer was in contact with four people after he started exhibiting symptoms, authorities said. Ebola isn't contagious until someone has symptoms.
Three people - his fiancée and two friends - are being placed on quarantine and monitored, health officials said. The fourth person is a car service driver who had no direct contact with him and is not considered at risk.
Spencer also went for a three-mile jog and visited a bowling alley in Brooklyn prior to feeling symptomatic, according to Bassett.
The bowling alley closed Thursday as a precaution, but it said in a statement that health officials have determined there are no risks to customers.
He also traveled on three subway lines. "At the time that the doctor was on the subway he did not have fever ... he was not symptomatic," Bassett said.
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Four days after a man was diagnosed with Ebola in Dallas, the apartment where he stayed has not been sanitized, a cleaning crew contracted to do the job said. Four other people are still living there.
Thomas Eric Duncan became the first person diagnosed with Ebola on American soil when he was hospitalized this week after arrival from Liberia.
His partner and her family are in isolation at the apartment, which still has the sheets and towels Duncan used.
Before leaving his homeland, Duncan answered no to questions on whether he was exposed to the deadly virus, said Binyah Kesselly, board chairman of the Liberia Airport Authority.
Duncan had been helping Ebola patients, including caring for one at a residence outside the capital of Monrovia, Liberian community leader Tugbeh Chieh Tugbeh said.
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A video showing American journalist Steven Sotloff being beheaded by terror group ISIS is authentic, U.S. officials said early Wednesday.
The Islamic militant group released the video Tuesday.
It shows the second beheading of an American journalist in two weeks, and blames President Barack Obama's decision to conduct airstrikes against the militant group in Iraq for the killing.
"The U.S. intelligence community has analyzed the recently released video ... and has reached the judgment that it is authentic," said Caitlin Hayden, the spokeswoman for the National Security Council. "We will continue to provide updates as they are available,"
In the video, Sotloff kneels in the desert, dressed in an orange prison-style jumpsuit. A masked "executioner" lords over him, wielding a knife.
The journalist speaks; the executioner speaks.
And then the horrific happens: the victim is beheaded.
"It is almost the exact same choreography," said Peter Neumann, a professor at King's College London, comparing ISIS videos showing the deaths of journalists Sotloff and James Foley. A video of Foley's execution was released last month.
The executioner appears to be the same person. The location of the two killings also appears to be similar.
Neumann suspects they took place in or around the Syrian city of Raqqa, one of the safest areas for ISIS, which calls itself the Islamic State.
See more on this developing story on CNN.com
Residents of Ohio's fourth-largest city will have to wait a little longer to use their tap water.
Tests conducted by both the state and federal Environmental Protection Agency showed high levels of toxin levels in two neighborhoods in Toledo, Mayor D. Michael Collins said early Monday.
Instead of isolating the two neighborhoods, the Mayor said he'll keep the ban on drinking or using tap water in the entire city of Toledo until additional retests are completed. He declined to provide specifics on the name of neighborhoods in question and how high the toxin levels are.
"A majority of areas are satisfactory, but we have two areas of concern," he said at a news conference.
As many as 400,000 people were told not to consume, cook with or boil the tap water after a toxin called microcystin was found in the water supply Friday. Collins told reporters the advisories will remain in effect until further notice
Toledo's drinking water comes from Lake Erie, where a harmful algae bloom that causes microcystin has been growing.
The city has set up distribution centers for potable water, where members of the Ohio National Guard, fire officials and other first responders are giving out safe water.
About 350 Ohio National Guardsmen have been activated by the governor, according to a U.S. Defense Department official, adding that they have set up three Reverse Osmosis Water Purification Unit sites at two high schools and a police facility. The guardsmen have also delivered ready-to-eat meals, the official said.
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There's no shortage of evidence that shows pro-Russian rebels shot down a Malaysian jet in Ukraine last week, U.S. Secretary of State John Kerry said.
Malaysia Airlines Flight 17 fell from the sky in Donetsk on Thursday, killing all 298 people aboard.
There's video of a launcher with one surface-to-air missile missing, imagery showing the firing and intercepted calls with rebels claiming credit for the strike, Kerry said.
"We know from intercepts ... that those are in fact the voices of separatists," he told CNN's State of the Union on Sunday. "And now we have a video showing a launcher moving back through a particular area there out into Russia with at least one missing missile on it."
Kerry accused Russia of backing the separatists.
"This is the moment of truth for Russia. Russia is supporting these separatists. Russia is arming these separatists. Russia is training these separatists. And Russia has not yet done the things necessary in order to try to bring them under control," he said.
British Prime Minister David Cameron didn't mince words either on who was to blame. In an op-ed in The Sunday Times, he called the plane crash and its aftermath "an outrage made in Moscow."
Russian President Vladimir Putin fired back with a video statement posted on the Kremlin's official website early Monday, arguing that his country has been pushing for peace in Ukraine.
"We have repeatedly called on all parties to immediately stop the bloodshed and to sit down at the negotiating table. We can confidently say that if June 28 fighting in eastern Ukraine did not resume, this tragedy most likely would not have happened," he said. "However, no one should have the right to use this tragedy to achieve selfish political objectives. Such events should not divide but unite people."
He stressed that safety must be guaranteed for international experts investigating the crash.
"We must do everything to ensure their work has full and absolute security (and) ensure necessary humanitarian corridors are provided," Putin said.
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Embattled Toronto Mayor Rob Ford said he is taking a break from his re-election campaign to seek help for alcohol abuse - hours after a local newspaper reported on a new video that allegedly shows him smoking crack cocaine.
"It's not easy to be vulnerable and this is one of the most difficult times in my life," Ford said in a statement Wednesday. "I have a problem with alcohol, and the choices I have made while under the influence. I have struggled with this for some time."
The statement, provided to CNN by Canada's CTV News, comes after the Toronto Globe and Mail reported on the new video.
In the video purportedly filmed Saturday, the newspaper reports Ford is seen smoking what a drug dealer described to the paper as crack cocaine from a copper-colored pipe. Two Globe and Mail reporters viewed the video, and the publication said it was shot in what appears to be Ford's sister's basement.
The paper said the substance in the pipe could not be confirmed.
The video is part "of a package of three videos the dealer said was surreptitiously filmed around 1:15 a.m., and which he says he is now selling for 'at least six figures,'" the paper reported.
See the latest on "Early Start" and get MORE on this story on CNN.com.
A FedEx truck crossed a freeway and slammed head-on into a bus carrying students in Northern California, killing 10 people, authorities said Friday.
The collision Thursday evening killed both drivers, five students and three chaperones, said Lt. Bill Carpenter with the California Highway Patrol.
At least 34 people were taken to local hospitals, authorities said.
The bus was taking students from various Los Angeles-area schools to visit Humboldt State University in Arcata. The collision occurred in Orland, about 100 miles north of Sacramento.
In a statement, the university said it got word of the crash but was working to find out more details.
"Our thoughts and prayers are with everyone involved in the tragic accident on I-5 in California. We are cooperating fully with authorities as they investigate," FedEx spokeswoman Bonnie Kourvelas said.
The truck also sideswiped another car before crashing into the bus. The condition of the car's driver was unknown.
Tommy Chang, the instructional superintendent for the Los Angeles School District, confirmed there were local students involved. He declined to provide additional details.
"The first priority is informing parents," he said.
Potential leads on the missing Malaysian jetliner keep coming. So do the setbacks and frustrations.
Four orange objects spotted by aircraft searching for the plane in the treacherous Indian Ocean turned out to be fishing equipment, Australian officials said Monday.
Flight Lt. Russell Adams had described the objects found Sunday as the "most promising leads."
But on further analysis, they turned out to be fishing equipment, once again dashing hopes of finding the jetliner that vanished March 8.
"We are searching a vast area of ocean, and we are working on quite limited information," Australian Prime Minister Tony Abbott told reporters Monday. "Nevertheless, the best brains in the world are applying themselves to this task. ... If this mystery is solvable, we will solve it."
The area of the search is 254,000 square kilometers (98,069 miles) that 10 planes and 11 ships were searching Monday. It's the most vessels to comb the search area so far.
Search crews from various nations have found an array of potential leads, only to later shoot down any links to the missing plane. They've included dead jelly fish and other garbage floating in the southern Indian Ocean.
Race against time
With every passing minute, it becomes harder to find the flight data recorders and cockpit voice recorders. Batteries on the "pinger" - the beacon that sends a signal from recorders - are designed to last about 30 days.
Malaysia Airlines Flight 370 disappeared 23 days ago en route from Kuala Lumpur to Beijing.
An Australian ship fitted with a U.S. ping detector is set to join the search Monday in a desperate race against time.
The focus is on helping find the flight recorders. Find the pinger and you find the recorders. Find the recorders, experts say, and you are steps closer to solving the mystery of Flight 370. Flight data recorders capture a wide array of information, including altitudes, air speeds and engine temperatures.
Crews loaded an American pinger locator and undersea search equipment onto the Ocean Shield, an offshore support vessel of the Australian navy. The ship was originally set to depart Monday morning, but authorities said it would be delayed by several hours for an inspection.
It will take the ship up to three days to reach the search area.
But that's just one of the many hurdles.
Oceanographer Erik Van Sebille weighs in on the possibility of finding the data recorder for Flight 370.
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A crowded street at a popular festival in Austin, Texas, became a chaotic scene as a suspected drunk driver tore through the crowd, running over people and hitting other cars, leaving two people dead and others seriously injured.
Police eventually caught the driver after a foot chase, bringing him under control with a Taser. The 21-year-old suspect will be charged with two counts of capital murder, police said.
Authorities have not released names of the dead, but they were a Dutch man on a bicycle and a local woman on a moped, Austin Police Chief Art Acevedo said, correcting his earlier statement that the victims had been on a motorcycle.
MassiveMusic, a music agency with offices around the world, posted a statement on its website and Facebook page identifying the company's Amsterdam-based creative director, Steven Craenmehr, as a person killed Thursday in Austin.
"During the 8 years that Steven worked for MassiveMusic, we got to know him as an unstoppable force, full of life, love and laughter," the Facebook post said. "This is an irreplaceable loss for the MassiveMusic family, and we are grateful for the years we spent with him. Our thoughts are with Steven's family and friends."
People were jamming the street listening to music just after midnight Wednesday when the driver, attempting to flee police, plowed through a barricade into the crowd.
Close calls for many
Some people escaped by a matter of inches.
Pablo Vazquez said the suspect drove right past him.
"The car barely missed me ... I was less than a foot away," Vazquez told CNN's "New Day."
"I saw some folks die."
"It looked like something out of a movie," said Russ Barone. "A few people lying on the street ... with their friends around them trying to get them up, trying to get them back to life. Hopefully, they are."
He said the scene was grisly, with people bleeding in the streets.
"I've never seen nothing like it. I felt like I was at a war or something," Barone said. "I was down here for the music ... we were having the best time ever. And then it turned into the worst thing I've ever seen."
Twenty-three others were initially hospitalized, some with multiple internal injuries. Most of the victims are in their 20s, said Dr. Christopher Ziebell, medical director at the University Medical Center Brackenridge emergency department.
As of Thursday evening, 15 of the 23 people hospitalized had been released, according to Austin police. Two patients remained in critical condition, three were in serious condition and three others remained hospitalized with non-life-threatening injuries.
Ziebell said it was fortunate the incident occurred so close to the hospital, and he applauded the Travis County paramedics, who had just undergone training for a similar scenario, for their response.
The driver will face two counts of capital murder - Texas' highest offense punishable by the death penalty. The car hit pedestrians, a moped, a taxi, a bicycle and a van, Acevedo said.
The suspect also will face 23 counts of aggravated assault by vehicle, Acevedo said.
Austin police identified the suspect as Rashad Charjuan Owens. Police department Public Information Officer Jennifer Herber told CNN Thursday afternoon that formal charges against Owens were forthcoming.
The incident began when an officer noticed a man driving in the wrong direction on a one-way street shortly after midnight.
A patrol officer attempted to stop the car near a crowded gas station, Acevedo said. The driver, the chief said, acted as if he was pulling over into the gas station, but he continued through the parking lot and exited, accelerating down the street.
The officer attempting to pull him over couldn't follow him because the parking lot was so crowded, so he had to back his patrol car out, Acevedo said. Another officer working barricade control had to jump out of the driver's way as he accelerated for about two blocks, striking pedestrians and vehicles, the chief said.
A foot chase ensued, and an officer eventually caught the driver and used his Taser to subdue him, Acevedo said.
The incident lasted one minute, police said.
Photos and video posted to social media showed people sprawled on a street for about a block with first-responders kneeling over them. In one instance, paramedics are seen performing CPR.
Witnesses on a YouTube video said the car sped through the crowd, tossing some victims into the air and knocking others down.
Acevedo urged those posting videos on social media to turn them over to authorities instead.
South by Southwest is an annual event that features film, interactive and music festivals, and draws tens of thousands of people to the Texas capital every year.
In a statement on its website, SXSW organizers commended the first-responders and city agencies that assisted them and said their thoughts and prayer were with the victims and those affected.
"We will be making schedule and venue changes for programming in the surrounding area of last night's events. All other programming will continue as previously scheduled." the statement said.
CNN first learned of the incident via posts on Twitter.
Nelson Mandela, the revered statesman who emerged from prison after 27 years to lead South Africa out of decades of apartheid, has died, South African President Jacob Zuma announced late Thursday. CNN's Robyn Curnow reports.
Mandela was 95.
"He is now resting. He is now at peace," Zuma said. "Our nation has lost its greatest son. Our people have lost a father."
"What made Nelson Mandela great was precisely what made him human," the president said in his late-night address.
"We saw in him what we seek in ourselves."
Mandela will have a state funeral. Zuma ordered all flags in the nation to be flown at half-staff from Friday through that funeral.
Mandela, a former president, battled health issues in recent months, including a recurring lung infection that led to numerous hospitalizations.
With advancing age and bouts of illness, Mandela retreated to a quiet life at his boyhood home in the nation's Eastern Cape Province, where he said he was most at peace.
He was later moved to his home in the Johannesburg suburb of Houghton, where he died.
Despite rare public appearances, he held a special place in the consciousness of the nation and the world.
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