SEATTLE (Reuters) - A US soldier accused of killing 16 villagers in Afghanistan is due to be arraigned on Thursday on charges of premeditated murder, for which military prosecutors are seeking the death penalty. Robert Bales, a veteran of four combat tours in Iraq and Afghanistan, is accused of gunning down the villagers - mostly women and children - in their homes in two villages in Afghanistan’s Kandahar province. The shootings occurred over a five-hour period in March. It was one of the deadliest incidents the military has blamed on a rogue US soldier since the Vietnam War and strained US-Afghan relations. Prosecutors say Bales, 39, acted alone and with “chilling premeditation” when, armed with a pistol, a rifle and a grenade launcher, he left his base twice, returning in the middle of his rampage to tell a fellow soldier: “I just shot up some people.”