SAN BRUNO, Calif - Investigators still have not given a cause for last week's deadly gas main explosion in San Bruno.
A man who returned home to the blown out neighborhood Sunday, took this incredible video of the huge ball of fire ripping through the neighborhhood just after the explosion.
The footage was taken from a house balcony just behind the pipe.
As investigators try to learn what caused the explosion, questions have surfaced about the Pacific Gas & Electric pipe that blew.
A document outlining costs to replace the pipe says quote "the likelihood of a failure makes the risk of a failure at this location unacceptably high".