4 KIDS DIE AFTER DAD LEAVES LIGHTED BARBECUE IN HOME.

Byline: Debbie Pfeiffer Trunnell and Susan McRoberts Staff Writers

PICO RIVERA - A father distraught over his failing marriage turned his home into a ``gas chamber'' by leaving a barbecue smoldering inside overnight, killing four of his children and critically injuring two others, authorities said Wednesday.

Authorities first said the deaths and injuries appeared to be accidental, but later began an investigation into whether they were the result of a deliberate act.

Adair Garcia, 30, who worked as a splicing technician for Pacific Bell in Los Angeles, was listed in critical but stable condition Wednesday at Presbyterian Intercommunity Hospital in Whittier, where two sheriff's deputies sat outside his door.

Authorities first believed the father was using the black charcoal barbecue - left burning in the dining room - to heat the home and initially reported the deaths as accidental. However, natural gas at the house was functioning, and Southern California Gas Co. spokesman Peter Hildalgo said meter readings were normal.

That led investigators to suspect it might be a deliberate act.

``We're investigating this as a homicide,'' sheriff's homicide Lt. Don Bear said.

Carbon monoxide levels inside were measured at 214 parts per million, well above the 60 parts per million considered dangerous, county fire officials said.

``That barbecue had been burning for quite some time. In effect, it created a gas chamber,'' fire Inspector Ed Osorio said.

Killed were Brenda Garcia, 10, Jonathan Garcia, 6, Anthony Garcia, 2, and Cecelia Garcia, 4, county coroner's officials said. Two other children, girls ages 6 and 9 whose names were not released, also were in very critical condition at Harbor-UCLA Medical Center in Torrance.