After a 13-hour gruelling encounter, Pakistan security forces on Monday gunned down all 10 terrorists involved in the brazen attack on Karachi's Jinnah International Airport.

The outlawed Tehreek-e-Taliban Pakistan (TTP) has claimed the responsibility for the attack that took place just before midnight and left as many as 29 persons, including security personnel and civilians dead.

The TTP said the assault was in revenge to killing of its former chief Hakimullah Mahsud in a drone attack last year. The outfit also blamed the military of killing scores of women and children in recent bombing precision attacks in North Waziristan.

In a joint action by the Army, the Rangers, Airport Security Force and police, all ten attackers were killed, said officials. "Three of them blew themselves up in desperation when they surrounded by security forces," they said. Among dead were 11 Airport Security Force peronnel, two Rangers, four PIA officials and a policeman. As many 26 persons were injured in the attack.

After regaining control of the sprawling airport, spokesman for the paramilitary Rangers Sibtain Rizvi, told reporters, "The attack is over and we have cleared the area of all militants."

The Karachi airport has been reopened for passengers and all flight operations have been resumed. The terrorists, who entered the airport disguised as securitymen, were planning a lengthy siege of the key facility, said officials. The attackers disguised as ASF personnel entered the old Karachi airport terminal from two sides in batches of five each, were not immediately identified though some officials said most of them looked like Uzbek.

(With agency inputs)