Four people in Southern California were discovered dead Thursday in a van that was parked at a CVS store parking lot, according to a report by KTLA.

The man was identified as Phunyouphone Kanyavong, 41, while the woman and the two children, who were both under the age of 4, could not be immediately identified. The woman was believed to be his girlfriend, while the children, both still in diapers, were thought to be their kids.

The bodies were found when a woman noticed a foul smell coming from a Honda van. The van was known to frequent the Garden Grove area, with officials noting the family slept in it at shopping centers and parks regularly.

Orange County police did not name a cause of death upon the discovery of the bodies, but Lt. Carl Whitney suggested that the use of a heater overnight led to carbon monoxide poisoning. People have died of carbon monoxide poisoning in an outdoor vehicle before, like a Kentucky couple in 2015.

The deaths of Kanyavong and his family was a stark reminder of the increasingly dire state of homelessness in Southern California. More than 700 homeless people in February were forced out of an encampment in the nearby Santa Ana riverbed, though they were given vouchers for shelters and motels in the area.

Still, per KTLA, the vouchers expired Friday, leaving many uncertain as to where they would stay for the foreseeable future. A court hearing Saturday ended with the county agreeing to extend some motel stays, as well as house some people at a civic center. It was uncertain if Kanyavong’s family stayed at the riverbed encampment, but they were found just a few miles away from it.

GettyImages-925969624 A homeless family was found dead in a van, possibly of carbon monoxide poisoning. A homeless man sits on a bench near a store with Oscars statues for advertising ahead of the 90th annual Academy Awards week, in Hollywood, California, on March 1, 2018. Photo: ANDREW CABALLERO-REYNOLDS/AFP/Getty Images