Attack Under Way at Airport

For the second time in two days, Pakistan's largest and busiest airport was forced to shut down after militants launched a brazen attack on airport security forces.

Tuesday's assault targeted the Airport Security Forces camp near Karachi's Jinnah International Airport, the airport's manager told CNN's Saima Mohsin.

It was not immediately clear how the militants were carrying out their attack or how many casualties may have resulted. At least 30 ambulances rushed to the scene, Mohsin said.

Late Sunday night, 10 militants stormed the same airport's cargo area, leading to an hours-long assault that left 36 people dead.

The Pakistani Taliban claimed responsibility for that assault, saying the attack was retaliation for the death of former chief Hakimullah Mehsud, who was killed in a U.S. drone strike in November in North Waziristan.

The militant group, also known as the TTP, had warned of more carnage starting Tuesday.

Shahidullah Shahid, another TTP member, said earlier this week that the group would engage "in a full-out war with the Pakistani state, starting on June 10."

But the airport itself is safe, Pakistan's Civil Aviation Authority said Tuesday.

"#Jinnah Airport is safe, #ASF academy is under attack,"the aviation authority tweeted Tuesday.

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