Pakistani military commandos early Sunday rescued 25 people who were held hostage by a group of armed militants inside the military headquarters for nearly 20 hours, the army spokesman said.

Pakistani security force stand guard at the entrance of the army headquarters in the garrison city of Rawalpindi, northeast Pakistan's Punjab Province, Oct. 10, 2009. [Xinhua Photo]

Major General Athar Abbas said that the operation released 25 hostages while three other hostages were killed.

He said that four militants were killed in the operation launched at 6:00 a.m. local time (0000 GMT).

He claimed that there is still one militant at large in a building held by the militants since Saturday.

Abbas said that two armed men were also wearing suicide jackets but they could not explode the bombs due to quick action by the army commandos.

The commandos started clearance operation after the rescue operation was over.

Witnesses said that they heard two or three explosions as the commandos stormed the compound where some two dozen security men and civilian employees were held in the army headquarters in the garrison city of Rawalpindi, some 30 km from the capital, Islamabad.

There had been intermittent firing after the first two explosions, they said.

Helicopters of Pakistani security force are on patrol near the army headquarters in the garrison city of Rawalpindi, northeast Pakistan's Punjab Province, Oct. 10, 2009. Armed militants, who had attacked two army check posts and killed six soldiers, have held up to 15 security men hostage at the army headquarters, while the security forces are trying for their safe release. The armed militants attacked two check posts outside the army headquarters at 11:30 a.m. local time (0530 GMT). At least six Pakistani soldiers and four suspected militants were killed in gunbattle.[Xinhua Photo]

The army spokesman said that the gunmen had exchanged fire with the commandos for a long time.

Army helicopters were also seen hovering over the army headquarters as the commandos launched pre-dawn operation, witnesses said.

On Saturday, a group of over 10 armed militants, wearing army uniforms, attacked two army check posts and killed six soldiers, and then held several security men hostage at the army headquarters.

Interior Minister Rehman Malik congratulated on the successful operation to get hostages free. He confirmed that four terrorists were killed in the morning operation.

He said that the attackers had been living in a house in the outskirts of Islamabad for two months and had planned the attack there.

Pakistani Taliban have claimed responsibility for the attack, which also killed six soldiers including two ranking officers.