CARACAS — A huge explosion rocked Venezuela's biggest oil refinery early Saturday, killing at least 24 people and injuring more than 50 others in the deadliest disaster in memory for the country's key oil industry. Balls of fire rose over the Amuay refinery, one of the largest in the world, in video posted on the Internet by people who were nearby at the time. Those killed included a 10-year-old boy, and at least 53 people were injured, Falcon state Gov. Stella Lugo said on state television. She said firefighters had controlled the flames at the refinery on the Paraguana Peninsula in western Venezuela, where large clouds of smoke were rising. At least 24 people were killed, many of them National Guard troops stationed at the refinery, Vice President Elias Jaua said on television after traveling to the area. He said the authorities were “trying to save the greatest number of lives." Oil Minister Rafael Ramirez said that Venezuela has enough fuel supplies to guarantee continued exports and domestic supply. As far as fuel shipments, he said, “we won't have major effects." The blast occurred when a gas leak created a cloud that ignited, Ramirez said. Some nearby houses were damaged by the blast, he said on television. “That gas generated a cloud that later exploded and has caused fires in at least two tanks of the refinery and surrounding areas," Ramirez said. “The blast wave was of a significant magnitude." Images in state media showed the flames casting an orange glow against the night sky. One photograph showed an injured man being wheeled away on a stretcher. “The areas that had to be evacuated were evacuated," Lugo said, according to the state-run Venezuelan News Agency. “The situation is controlled. Of course they're still a fire rising very high, but ... the specialists tell me there is no risk of another explosion." Ramirez said oil workers will determine what caused the gas leak and were inspecting the damage along with troops. Ramirez said that nine storage tanks were damaged. He said supplies of fuel had been cut off to part of the refinery, and that the fire had been brought under control. — AP