ISLAMABAD - Gunmen attacked one of Pakistan's biggest airports in Karachi on Sunday, killing at least five people, police said.

"The old terminal of Karachi airport was attacked by militants," said a senior police official.

Officials in Karachi, Pakistan's commercial hub, said all flights had been diverted.

"All flights destined for Karachi have been diverted to other cities," said a civil aviation authority spokesman.

No one immediately claimed responsibility for the attack.

"Over half a dozen armed men made towards the runway from the backside of the airport," said a private television channel, quoting a witness.

Please LIKE our Facebook page - it makes us stronger