Gunmen in Nigeria have killed dozens of people and kidnapped a number of children in separate attacks in two northern states, police and residents said on Sunday, the latest incidents in a region dogged by armed violence. Four killed after US convoy attacked in Nigeria The gunmen also abducted several children who were collecting firewood in a forest in neighboring Gora village. In north central Benue state, gunmen killed 25 people and set their houses on fire during an attack on Saturday on the Imande Mbakange community, two residents said