Pakistani fighter jets have bombed Taliban strongholds in the lawless northwest tribal belt, killing at least 31 suspected militants, government and security officials said Monday. The air strikes came after a militant hostage siege at army headquarters near Islamabad left 19 people dead at the weekend, and as the military prepares for an offensive in the tribal region bordering Afghanistan. "Jet fighters bombed various Taliban hideouts in Mamoond district of Bajaur," local government official Manasib Khan told media, referring to a district north of the provincial capital Peshawar. "The latest reports said that at least 12 militants were killed and nine were wounded in the air strikes," he said, adding that Taliban trenches on mountaintops and underground hideouts were targeted by the war planes. "Ground troops are also using artillery to pound militant positions in Mamoond area," Khan said. An intelligence official at Khar, the main town in Bajaur, confirmed the air strikes and death toll. Fighter jets also bombed Taliban strongholds in South Waziristan, the semi-autonomous tribal district believed to be the target of an upcoming operation against the Tehreek-e-Taliban Pakistan network linked with Al-Qaeda. "Pakistan fighter jets bombed hideouts at Makeen and Ladha towns," Syed Shahab Ali Shah, the area's top administrative official, told media. A security official in South Waziristan's main town Wana said: "We have reports that at least 19 militants were killed in both Makeen and Ladha."