The United States is doing what it must to "take the fight to terrorists," leading a coalition of Arab nations in a series of airstrikes against the so-called Islamic State terror group in Syria, U.S. President Barack Obama said Tuesday.
At the same time, the United States took action - on its own - against another terrorist organization, the Khorasan Group. Obama described its members as "seasoned al Qaeda operatives in Syria."
U.S. officials said the group was plotting attacks against the United States and other Western targets.
The plots against the United States were discovered by the intelligence community in the past week, an intelligence source with knowledge of the matter told CNN. The source did not say what the target may have been, but said the plot potentially involved a bomb made of a nonmetallic device like a toothpaste container or clothes dipped in explosive material.
A plot involving concealed bombs on airplanes "was just one option they were looking at," a U.S. official said.
"Once again, it must be clear to anyone who would plot against America and try to do Americans harm that we will not tolerate safe havens for terrorists who threaten our people," Obama said in televised remarks from the White House.
Concern over a possible backlash by the terror groups has prompted the U.S. Department of Homeland Security to issue a bulletin warning law enforcement agencies to be on heightened alert for lone-wolf terror attacks on U.S. soil in wake of the airstrikes, a U.S. law enforcement official with knowledge of the warning told CNN.
The bulletin calls for vigilance as well as scrutinizing social media for anyone encouraging violence in response to the strikes, according to a U.S. law enforcement official with knowledge of the warning's contents. It points to the use of social media as a tactic by ISIS to spread its message and call for violence.
It also advises agencies to look for changes in appearance or behavior in those they're tracking, the official said.
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A U.S. airstrike near Baghdad on Monday marked a new phase in the fight against ISIS.
The airstrike southwest of the city appears to be the closest the U.S. airstrikes have come to the capital of Iraq since the start of the campaign against ISIS, a senior U.S. military official told CNN. And U.S. Central Command said in a statement that it was the first strike as part of "expanded efforts" to help Iraqi forces on the offensive against ISIS.
Monday's airstrike destroyed an ISIS fighting position that had been firing at Iraqi forces, Central Command said.
It occurred about 35 km (22 miles) southwest of Baghdad, another U.S. official said.
The United States began targeted airstrikes against ISIS in Iraq last month to protect American personnel and support humanitarian missions. Last week, U.S. President Barack Obama said new airstrikes would aim to help Iraqi forces on the offensive against the Islamist militants.
Obama also said airstrikes would include ISIS targets in Syria. And last week he also asked Congress for authorization to train and equip moderate Syrian rebels.
The authority comes under Title 10 of the U.S. code, which deals with military powers, and Congress could vote on granting it this week. Approval also would allow the United States to accept money from other countries for backing the Syrian opposition forces.
A senior administration official told reporters Monday that Obama has been making calls to Democratic and Republican members of Congress, asking them to pass the authorization.
U.S. Secretary of State John Kerry courted Middle Eastern leaders over the weekend to join a coalition in the fight against the Islamist militant group, which calls itself the Islamic State.
More than two dozen nations, the Arab League, the European Union and United Nations met in the French capital Monday, calling ISIS a threat to the international community and agreeing to "ensure that the culprits are brought to justice."
The United States has conducted more than 150 airstrikes in Iraq against ISIS, and Kerry has said nearly 40 nations have agreed to contribute to the fight against the militants. But it remains unclear which countries are on that list and the precise roles they'll play.
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An audio recording purportedly from the Islamic State of Iraq and Syria promises more fighting in more Iraqi cities, including Baghdad.
"Continue your march as the battle is not yet raging," a voice said to be that of ISIS spokesman Abu Mohammed al-Adnani says on the message posted early Thursday (last Wednesday night ET) on the group's media website.
"It will rage in Baghdad and Karbala. So be ready for it."
CNN cannot confirm the authenticity of the audio or time and date of its recording, which is nearly 17 minutes long.
"Don't give up a hand's width of ground you've liberated," the voice says in apparent encouragement of ISIS fighters.
The message, if authentic, is further proof that the militant group are not content with control of the places they have already taken over - and are setting their sights higher.
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