Nigeria's military killed eight Islamist insurgents who attacked a market in the volatile northeastern city of Maiduguri on Monday, and deactivated three bombs in controlled explosions, the spokesperson for the joint military task force (JTF) said. The Maiduguri-based sect Boko Haram is waging an increasingly violent insurgency against the Nigerian government, striking beyond its north-eastern heartland to hit targets across the north and in the capital, Abuja. "The JTF has killed eight BH (Boko Haram) members this afternoon who attacked and wounded three civilians at the Baga Road market," Lieutenant Colonel Hassan Mohammed said in a statement. "The sect members were engaged in a shootout." The sect, which wants sharia law to be more widely applied across Africa's most populous nation, has become increasingly sophisticated and deadly in its methods over the last six months, often setting off multiple bombs in succession or following them up with shooting sprees. "The civilians wounded have been taken to hospital where they are receiving treatment while the market has been cordoned off," Mohammed said, adding that troops had deactivated three explosive devices. A bomb exploded near a church in the Nigerian town of Suleja, on the edge of the capital, Sunday, wounding five people in an attack that bore the hallmarks of the sect. On Wednesday, gunmen suspected to be from Boko Haram stormed a prison in Kogi state in central Nigeria, killing one warden and freeing 119 prisoners, the prison authorities said. Although the majority of the sect's attacks still occur in its home base in the northeast, its threat has spread and become more lethal. At least 178 people were killed in its most deadly attack last month in Nigeria's second biggest city, Kano.