AlHijjah 9, 1432, Nov 5, 2011, SPA -- Colombian security forces killed the leader of the country's largest socialist militant group, FARC, UPI quoted the president and defense minister as saying Saturday. Photographs of the body of a beardless Alfonso Cano were shown on state television along with a statement from President Juan Manuel Santos confirming the 63-year-old rebel leader's death. "It is the most devastating blow that this group has suffered in its history," Santos said. "I want to send a message to each and every member of that organization: demobilize ... or otherwise you will end up in a prison or in a tomb." Colombia News said the military raid on the rebels' jungle camp also resulted in the arrest of Cano's chief bodyguard in a mountainous region in the southwestern state of Cauca. FARC, which stands for Revolutionary Armed Forces of Colombia in Spanish, gathered momentum in the early 1980s as a Marxist-Leninist armed militia. Cano took over the movement in 2008 when its former leader died of a heart attack, the BBC said.