14 may have been forcibly conscripted into the armed forces during recruitment sweeps. About 40% of the Bolivian army was believed to be under the age of 18, with half of those below the age of 16. , Bolivia invites children to begin their adult conscription early, from age 17. Brazil In Brazil the local organized crime groups, such as Comando Vermelho, recruit children to sell drugs and commit homicides, as well as to fight with the police and other rival groups. Also the Brazilian militias recruit children to fight in the conflict against Comando Vermelho. Canada In Canada, people may join the reserve component of the Canadian Forces at age 16 with parental permission, and the regular component at 17 years of age, also with parental permission. They may not volunteer for a tour of duty until reaching age 18. Colombia In the Colombian armed conflict, from the mid-1960s to present, one-fourth of non-state combatants have been and still are under 18 years old. In 2004 Colombia ranked fourth in the world for the greatest use of child soldiers. There are currently 11,000–14,000 children in armed groups in the country. In negotiations with the government, armed groups have offered to stop the recruitment of minors as a bargaining chip, but they have not honoured these offers. Bjørkhaug argues that most child soldiers were recruited through some combination of voluntary participation and coercion. In 1998 a Human Rights Watch press release indicated that 30 percent of some guerrilla units were made up of children and up to 85 percent of some of the militias, which are considered to serve as a "training ground for future guerrilla fighters", had child soldiers In the same press release it was estimated that some of the government-linked paramilitary units consisted of up to 50 percent children, including some as young as eight years old. In 2005 an estimated 11,000 children were involved with left- or right-wing paramilitaries in Colombia. "Approximately 80 percent of child combatants in Colombia belong to one of the two left-wing guerrilla groups, the FARC or ELN. The remainder fight in paramilitary ranks, predominately the AUC." According to P. W. Singer the FARC attack on the Guatape hydroelectric facility in 1998 involved militants as young as eight years old and a 2001 FARC training video depicted boys as young as 11 working with missiles. The group has also taken in children