Pakistan: 'Taliban vows 'full-out war'... More violence erupts near Pakistan's busiest airport

By Holly Yan and Sophia Saifi

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 academy near Karachi's Jinnah International Airport, the airport's manager told CNN's Saima Mohsin in Karachi.

Gunfire rang out in the area, but it was not immediately clear how many casualties may have resulted. At least 30 ambulances rushed to the scene, Mohsin said.

Once again, the Pakistani Taliban claimed responsibility.

"This wave of attacks will be continuing in retaliation for the shelling and atrocities of the government," spokesman Shahidullah Shahid said by phone Tuesday from an undisclosed location. Ten militants stormed the same airport's cargo area late Sunday night, leading to an hours-long siege that left 36 people dead, including the assailants.

The Pakistani Taliban also 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. Shahid said earlier this week that the Pakistani Taliban would engage "in a full-out war with the Pakistani state, starting on June 10."

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

"#Jinnah Airport is safe, #ASF academy is under attack," the aviation authority tweeted Tuesday. The Civil Aviation Authority said flights were temporarily suspended but later resumed Tuesday. By Tuesday afternoon, the situation was "under control," military spokesman Asim Bajwa said.

"3 to 4 terrorists fired near ASF Camp, ran away," Bajwa tweeted. "No breach of fence, no Entry. Chase is on, situation under control."

Airstrikes kill 15 militants Hours before the renewed violence in Karachi, the Pakistani military launched a deadly assault targeting nine militant hideouts Tuesday.

At least 15 militants were killed in the airstrikes on Khyber Agency, in tribal areas bordering Afghanistan, the Pakistani military said.

A military spokesman said he could not confirm whether the airstrikes were directly related or in response to the violence at Karachi's airport earlier this week.

But it's those kinds of attacks that the Pakistani Taliban warned would spur more violence from their end. When the TTP claimed responsibility for Sunday's airport attack, it called on the government to end airstrikes -- or face more attacks like the Karachi airport terror attack.

Apparently, the TTP followed through with its promise. History of terror The Pakistani Taliban, formally known as Tehreek-i-Taliban Pakistan, has long conducted an insurgency against the Pakistani government.

"Their primary target is the Pakistani state and its military," said Raza Rumi of the Jinnah Institute, a Pakistani think tank. "It resents the fact that (Pakistan) has an alliance with the West, and it wants Sharia to be imposed in Pakistan." The U.S. Justice Department charged Mehsud in 2010 for his alleged involvement in a 2009 bombing at the United States' Forward Operating Base Chapman in Khost, Afghanistan. The attack killed seven U.S. citizens, including five CIA officers and a member of Jordanian intelligence.

Mehsud took over from Baitullah Mehsud, a fellow clan member, in 2009 after the latter was killed in a U.S. drone strike. Four years later, Hakimullah Mehsud suffered the same fate.