At least six militants were killed while eight soldiers including two officers injured during ongoing military operation in Pakistan's South Waziristan tribal area in the last 24 hours, an army statement said Thursday.

On Shakai-Kaniguram axis, militants fired with small arms on security forces and five soldiers including an officer were injured. During exchange of fire, six militants were killed, the Inter Services Public Relations said in the daily press release.

Security forces carried out search operation on Razmak--Makeen axis and destroyed eight bunkers. A large quantity of arms and ammunition were recovered.

On Jandola-Sararogha axis, three soldiers were injured including an officer by improvised explosive devices when security forces were patrolling the area.

In Swat and Malakand area of North West Frontier Province, security forces conducted search operation and apprehended four suspects. Other four suspects voluntarily surrendered themselves to security forces at Charbagh.

According to the National Database and Registration Authority, about 275,000 people fled the tribal area before and during the military operation.

According to the army statistics, Pakistani security forces have killed more than 500 militants since they launched the ground assault on Oct. 17 in the South Waziristan, advancing towards the main base of Taliban militants in Pakistan. The army said that about 30,000 soldiers are in place to take on an estimated 10,000 hard-core Taliban militants in the lawless area.

The military said that the operation was launched in six towns of the area in three directions and is likely to continue for six to eight weeks, but no final deadline can be given.