Suspected militants dressed in army uniforms attacked Pakistan's army headquarters today, killing four guards and triggering a battle in which four gunmen were killed.
The attack on the tightly guarded headquarters in the city of Rawalpindi came as the army prepares a major offensive against Pakistani Taliban militants in their northwestern stronghold on the Afghan border.
The gunmen drove in a white van to a main gate at the sprawling complex, opening fire and throwing at least one grenade when challenged, security officials said.
The gunmen then exchanged fire with soldiers for about 40 minutes. Four gunmen and four guards were killed but two of the gunmen escaped, military officials said.
"Two terrorists are still missing, a search operation is on," said a military official who declined to be identified.
Another military official said some firing had been heard and a helicopter was helping in the search for the two gunmen.
Dawn television said the fleeing gunmen had taken two military men hostage.
Al Qaeda-linked Islamist militants have launched numerous attacks in Pakistan over the past couple of years, most aimed at the security forces and government and foreign targets.
The militants have attacked military targets in Rawalpindi before. Television pictures showed the militants' white van, its doors open, where the gunmen abandoned it by concrete barriers outside the gate.