The Region - News from July 13, 1986

Authorities said an explosion that critically burned a woman and her three children at a Pomona shopping mall was triggered by a faulty switch in an underground electrical vault. The blast blew 7-year-old Shawna Williams 25 feet into the air, then turned into a fireball that burned her mother, brother and sister and left them in critical condition. A spokeswoman for the Southern California Edison Co. said the explosion was set off by the malfunctioning of a 12,000-volt switch that ignited oil covering several underground transformers at the Indian Hill Village mall.