At least six people were taken to the hospital Thursday morning after a massive explosion caused a large fire in Hayward, California, fire officials say.

The leak in Hayward, Calif., started after a construction crew struck a Pacific Gas and Electric underground gas line, according to the utility.

Residents in the area said the explosion was thunderous, shaking their homes. They could hear the boom from the explosion and see the fire.

SAN FRANCISCO — A gas explosion set off a major fire in a San Francisco Bay Area neighborhood on Thursday after obliterating at least one home, blowing out windows and shaking nearby houses. Six ...