Frank Huddleston, an investigator at the Ontario, Calif., fire department, suspects the phone's battery, its original, is to blame for the accident, which occurred Thursday morning. He stressed that the exact cause is still to be determined.
The U.S. Consumer Product Safety Commission (CPSU) made aware of the event, has yet to decide what to do, a spokesman for the group said.
Verizon Wireless, which sold the phone, is seeking out the California girl's family to learn more, according to company spokeswoman Brenda Boyd Raney. "Reports of this nature get the highest levels of attention and follow-up," she said.
Phone maker Kyocera Wireless did not return calls seeking comment.
The incident is not the first time that a cell phone has either overheated or exploded in the United States--and it's not the first reported instance of a Kycera phone malfunctioning. All of the incidents have raised concerns over the safety of a device jammed into pockets, handbags or pressed against a person's face.
Late last month, Verizon Wireless recalled 50,000 cell phone batteries, some of which may be counterfeit, after reports suggested that they may cause minor fires and injuries. The TM-510 batteries, which carry the LG Mobile Phones brand, don't have the circuitry normally installed to prevent overcharging, according to CPSC.
In October 2003, Kyocera temporarilyof its KE413 Phantom phone after one sold by Cricket Wireless vented hot gasses, scaring but not injuring a consumer in Omaha, Neb. Kyocera determined it was an isolated problem and began selling the phone a week later.
In January, the CPSC issued itsof cell phone batteries, some 40,000 from Coslight International Group in Hong Kong. The batteries were on four phones, all Kyocera Wireless models that overheated. One person was slightly injured from the defect. The batteries were also available from Verizon Wireless and Alltel.
Witnesses to the latest mishap said the 16-year-old girl had the phone in her back pocket, when her phone let out a whoosh, bulged, then shot out flames and smoke. She was treated for second-degree burns at an area hospital and was released shortly afterwards.
Huddleston said there wasn't a stove or other source of flame nearby at the time, and pre-July Fourth firework pranks have been ruled out. Witnesses saw flames coming from the bottom of the phone, where vents are installed to prevent overheating batteries from exploding. The battery, once wafer-size, was "the shape of a sausage with one end open," Huddleston said.