By Da Lin

RICHMOND (CBS SF) – A couple who perished in a residential fire possibly caused by fireworks in Richmond early Friday morning have been identified and their son remains in critical condition in a San Francisco hospital, authorities said.

A man identified as Mearn Lee Pom, 56, and a woman identified as 50-year-old Bounkeo Viengvilai were killed in the blaze, a Contra Costa County deputy coroner said.

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The fire, reported at 2:37 a.m., broke out in the converted garage where the couple lived with their son behind a main residence in the 600 block of 21st Street, according to fire officials.

Firefighters say the people living in the house were playing with fireworks in the street, and in the backyard where the home burned down.

The son, who was believed to be 26 years old, was being treated for critical injuries suffered in the fire, Richmond fire Battalion Chief Manly Moulton said.

Firefighters arriving on the scene of the one-alarm blaze saw the garage fully engulfed in flames.

The son was found outside of the building and was rushed to a burn unit at Saint Francis Memorial Hospital in San Francisco, Moulton said.

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Firefighters found the two remaining residents inside the garage and attempted life-saving procedures, but the man and woman were pronounced dead at the scene, Moulton said.

Crews were able to get the fire under control within about 15 minutes and no firefighters were injured, he said.

The victims were part of a family of eight living on the property, with the parents and son living in the roughly 30-by-30-foot garage and five other relatives in a main house, Moulton said.

Investigators remained on the scene late Friday morning to determine what caused the fire.

The battalion chief said he did not know whether the garage, which was completely destroyed in the fire, had smoke detectors.

The blaze caused an estimated $35,000 in damage, he said.

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