At least 14 people were killed early Saturday when three cars of attackers pulled up and opened fire on a Brazilian nightclub, authorities said. At least six other people were injured in the attack on the Forro do Gago club in the city of Fortaleza. Witnesses cited in local media said armed men poured out of three cars in front of the venue before firing into the building shortly after midnight. The attackers reportedly fired rounds for about a half hour before finally fleeing. Andre Costa, the security secretary for Ceara state, said at a press conference after the shooting that the motive has not yet been determined. Investigators are looking into whether the incident was part of an ongoing feud between rival drug gangs, he said.