A man critically burned in a San Fernando Valley apartment building explosion says he´s the one who caused it. A city fire official says Dennis Cohen told investigators he disconnected a gas line between a wall and a stove. The 47-year-old Cohen says that he later lit a cigarette in a bathroom, setting off the blast. Cohen´s in critical condition with burns to 60 percent of his body. The explosion damaged about a dozen apartment units, but Cohen was the only one to suffer serious injury. It´s not clear why he disconnected the gas line.