(Scroll down to watch CBS News Correspondent John Blackstone's report)
At least four people died in the fire caused by the explosion, CBS News Correspondent John Blackstone reports. Fifty were hurt with eight in critical condition. Thirty-eight homes were destroyed, and dozens were damaged. Twenty five percent of the neighborhood remained too hot and dangerous for firefighters to enter Friday afternoon. Cadaver dogs have been brought in to search for the missing.
One San Bruno resident named Priscilla told Blackstone that an odor was recently present in the devastated neighborhood.
"In the past week or so we've had the really strong smell of gas," she said.
Another Californian told Blackstone she smelled the same odor near a house destroyed in the blaze.
"Right at that house on the corner that had the beautiful little water fountain which is now all gone, that's where I smelled it," she said.
A 44-year-old woman and her young daughter are among those feared dead in the explosion.
Officials have not released any names of the victims.
Agustin Macedo of San Francisco told The Associated Press on Friday that his 44-year-old daughter, Jacqueline Greig, and his granddaughter were killed. Reached by phone, Macedo said he was too upset to give any more information, including how he knew his family members' fate. The granddaughter's age and name weren't known.
Greig lived in a house just yards from the source of the blast.
Greig worked at the California Public Utilities Commission. Executive Director Paul Clanon announced to staff Friday morning that Greig was missing.
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