A local fire chief says a gas line explosion likely caused the massive fire burning homes in a residential neighborhood south of San Francisco.

San Bruno Fire Chief Dennis Haag says he believes a high-pressure gas line blew just after 6 p.m. Thursday.

Pacific Gas and Electric says the utility company is looking into the possibility of a natural gas explosion, but he has no further details.

Live television footage showed more than a dozen homes destroyed, with flames reaching as high as 60 feet in the air as the fire incinerated everything in its path.

A person who answered the phone at Seton Medical Center in nearby Daly City says the hospital is on a triage alert as the injured are brought in.