Gunmen raided a rural farm in southern Colombia and killed nine farmers, including four children, in an attack which authorities blamed on the nation's largest rebel group. Col. Harold Martin Lara, chief of police in Putumayo state, told Caracol Radio on Sunday that the assailants belong to the Revolutionary Armed Forces of Colombia, or FARC. He said the owner of the farm where the two families had lived "received threats for refusing to pay bribes to the guerrillas." The farmers were killed after attending a church service near the town of Puerto Asis, a longtime stronghold of the FARC - Latin America's oldest and most potent leftist insurgency. A 13-year-old girl who was asleep at the time survived, Lara said. The attack was the second in a week blamed on the rebels. Authorities said 70 FARC members went house-to-house Tuesday in the remote village of Currulao with a list of names, killing three women and two men.