Six people have been taken to hospitals after a gas explosion started a major fire in a San Francisco Bay Area suburb. The explosion in the city of Hayward obliterated at least one home and sent heavy smoke into the air. Fire officials said six people were taken to hospitals. Video shows a home sitting under a blue sky before it suddenly exploded, sending wood and debris skyward. A spokesperson for Pacific Gas & Electric Co. said construction workers damaged an underground gas line around 7:35 a.m. Thursday. The utility stopped the gas flow at 9:25 a.m. The explosion occurred shortly afterward.