Up to nine civilians were killed and 22 others wounded Monday morning when a passenger bus was struck by a roadside bombing in eastern Afghan province of Wardak, the country\'s Interior Ministry confirmed.\"Nine innocent civilians, including a woman, were martyred and 22 others wounded when a passenger bus ran over a roadside mine in Salar area of Warkak province at around 8:20 a.m. Monday,\" the ministry said in a statement.Two women were among the injured, it added.The statement blamed the Taliban insurgents for the bombing in the province 35 km west of Afghan capital Kabul.The insurgent group has been largely relying on roadside bombing and suicide attacks in fighting Afghan security force and NATO-led troops based in Afghanistan, often causing civilian casualties.The Taliban has yet to make comments.A total of 2,754 civilians were killed and 4,805 injured in conflict-related violence in 2012, a 12 percent drop in overall civilian casualties compared with 2011, according to a UN report released in February in Kabul.The UN report attributed 81 percent of the civilian deaths to the attacks of Taliban insurgents and other armed groups opposing the Afghan government, another 8 percent of the deaths were attributed to Afghan and NATO-led forces and 11 percent were unattributed.