At least 45 people were killed in a double suicide blast outside Pakistan's main military arms factory on Thursday, police said.

"There are 45 people confirmed dead in the blast. The number of injured is very high and we are right now collecting information," local police official Sardar Shahbaz Hussain told AFP.

Police said two bombers blew themselves up outside the gates of the factory at Wah, near Islamabad as workers left after a shift change.

AFP