Masked gunmen fired indiscriminately on people at a bus terminal in Medellin, killing at least 16 and wounding four. In another attack outside the city, four people died when gunmen raided a ranch before dawn. Police suspect the massacre at the bus terminal was carried out by a criminal gang that is feuding with urban militias linked to leftist guerrillas. Witnesses said about 10 gunmen, who fled in cars after the shooting, asked their victims where the militia chiefs were before opening fire, said Gen. Alfredo Salgado, head of the Medellin police. "It makes us suspect this was about vengeance," Salgado said. Three members of the gang suspected in the attack were killed in a shootout earlier in the week. No suspects were identified in the predawn attack.