Although there are no exact figures, hundreds of thousands of children under the age of 18 serve in government forces or armed rebel groups. Some are as young as eight years old. Since 2001, the participation of child soldiers has been reported in 21 on-going or recent armed conflicts in almost every region of the world. Children are uniquely vulnerable to military recruitment because of their emotional and physical immaturity. They are easily manipulated and can be drawn into violence that they are too young to resist or understand. The problem is most critical in Africa, where children as young as nine have been involved in armed conflicts. Children are also used as soldiers in various Asian countries and in parts of Latin America, Europe and the Middle East.