A massive explosion and fire that erupted late Thursday in a residential neighborhood south of San Francisco killed at least four people, injured dozens more and destroyed over 53 homes.
Updated Friday at 7:34 a.m.
Jeff Smith, a spokesperson for Pacific Gas and Electric, said that a natural gas pipeline ruptured in the area of the blast leaving a huge crater, but that the cause of the explosion was still under investigation.
"If it is ultimately determined that we were responsible for the cause of the incident, we will take accountability," Smith said in an e-mail statement.
The company shut down power to the entire area surrounding the San Bruno neighborhood where the explosion occurred shortly after 6 p.m. Thursday night.
Residents there reported what felt like an earthquake, followed by an explosion so great that some thought a plane had crashed. Witnesses saw a fireball shoot 1,000 feet into the air. The fire quickly consumed homes in surrounding blocks.
Over 100 area residents evacuated to emergency shelters. Officials have no estimates as to the number of residents missing.
Late Thursday hundreds of firefighters had the fire 50 percent contained.
Fire officials say it will take crews until Friday afternoon to be able to search the area for people.
Governor Schwarzenegger is on a trade mission in Asia this week. Acting Governor Abel Maldonado declared a state of emergency in San Mateo County due to the San Bruno explosion and fire.