SAN BRUNO, Calif., Sept. 9 (UPI) -- Authorities in San Bruno, Calif., said they were evacuating a residential neighborhood where a huge fire was burning following an explosion Thursday.
The explosion occurred just after 6 p.m. PDT, sending a giant fireball 50 to 60 feet into the air and generating plumes of smoke that were visible for miles, the San Francisco Chronicle reported. It was unclear what caused the explosion but there has been speculation it might have involved a gas line.
A Pacific Gas and Electric Co. spokesman told the newspaper its crews were looking into whether one of its gas lines was feeding the fire.
"We just don't know exactly what sparked this," Kelly Huston of the California Emergency Management Agency told CNN.
Huston said firefighting crews were dropping fire retardant and water on homes and coordinating with firefighters on the ground in a "full-on" effort to contain the blaze. Video broadcast on CBS5.com, San Francisco, showed several houses in flames.
Huston said there were reports of some people being treated for injuries but it was not known how many people were injured.
Some witnesses told reporters they heard and saw an airplane crash just before the explosion just west of San Francisco International Airport but airport duty officer Michael Brown told the Chronicle the control tower indicated there was "no reason to suspect it's an aircraft" and airport authorities were not aware of any reports of missing craft.
A spokesman for the Federal Aviation Administration told the newspaper the FAA had no information indicating whether the fireball was related to a plane crash.
