Security forces killed four suspected militants overnight in a northwest Pakistani tribal region where the military has waged an offensive against insurgents, an official said Wednesday. The military launched its offensive in early August in the Bajur tribal region, which it has termed a «mega-sanctuary» for militants. Government official Jamil Khan said the main Bajur town of Khar is under curfew and that fresh troops were flowing in along with tanks and artillery. Khan said artillery attacks overnight killed four militants in the Charmang area. In other violence, militants fired rockets late Tuesday at a security post near Darra Adam Khel, another area of the northwest, killing two paramilitary troops and wounding three others, said Rashid Khan, a local government official. The troops responded with artillery fire, but it was unclear if there were any militant casualties, Associated Press reported.