Officials say the death toll from twin suicide attacks at the gates of Pakistan's main weapons complex has risen to 37.
The bombers struck Thursday just as workers were leaving the facility in Wah, a garrison city about 35 kilometers (20 miles) west of the capital, Islamabad.
Hospital official Mohammed Azhar says 37 people have died in the attack. Regional police chief Nasir Durrani says 50 more have been wounded.
Soldiers and police have cordoned off the area and prevented reporters from approaching. Ambulances are lining up on the road outside to deal with the casualties.
Security forces are involved in an escalating war with Islamic extremists in two nearby regions of northwestern Pakistan.