SAN BRUNO, Calif. (AP) - Residents have been allowed to return to the suburban San Francisco neighborhood blown apart by a natural gas pipeline explosion three days ago.
The utility responsible for the line says a segment near the explosion site was due to be replaced, because the section of San Bruno it ran through is considered a heavily urbanized area and the risk of failure was "unacceptably high."
But investigators still don't know what caused the blast.
They are also trying to confirm exactly how many people died in the blast and subsequent inferno.
The official death toll stands at four.
Five people are reported missing and at least 60 injured, some critically.
Nearly 50 homes were destroyed and seven severely damaged in the blast, while dozens of other homes suffered less severe damage in the fire that sped across 15 acres.