It happened at about 3 a.m. Sunday on the 2500 block of Manchester Avenue in San Pablo.
"One of my neighbors came knocking on the door saying, 'There's a fire. Get out," said neighbor Mary Lewis.
Lewis said she woke up to chaos early Sunday morning at her San Pablo apartment complex. An upstairs unit was on fire. Contra Costa Fire crews responded minutes later.
"I told them there were kids upstairs. There were three kids. They got two out. They didn't get other one. They brought him out, but he passed away," Lewis said.
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"Our crews identified heavy smoke and fire in the unit. They made entry and eventually located three victims who were pulled from the structure," said Captain George Laing from Contra Costa County Fire Protection District.
Laing says a 22-year-old man did not survive. Two minors in the apartment were taken to the hospital, suffering from burns and smoke inhalation. Neighbors say the victims were all related.
Lewis said a parent was working when the fire started.
"She works night shift, so I called to let her know her house was on fire and she came," Lewis said.
Neighbors say they woke to smoke and shattering glass with flames shooting out of the backside of the apartment unit.
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"The curtains caught on fire, then all of the sudden it went boom, and the window blew out," said William Keene. "I called the fire department right away."
Fire crews extinguished the fire quickly. The unit is now "red tagged." A cause of the fire is under investigation.
"A working smoke alarm will save lives," Laing said.
CORNELL BARNARD: "Were there smoke alarms in this unit?
CAPTAIN GEORGE LAING: "That's part of the investigation."
Laing says his department is mourning the loss of life in the fire.
"We feel deeply this loss, and we extend our condolences to family and relatives," he said.