Six people who died when a fire gutted a mobile home in central Louisiana were apparently trapped between flames and a door that was nailed shut, authorities said Monday.

Authorities said the bodies were found after firefighters extinguished the blaze that broke out around 4 a.m. Sunday at the home in the small community of Bob, La., about 170 miles northwest of New Orleans.

The fire started near the front of the mobile home where an addition was recently built and the victims were found in the rear where the back door had been nailed shut, State Fire Marshall investigators said in a release.

Investigators said they found no smoke detectors in the rubble and that they believe the victims died of smoke inhalation.

Three of the victims have been tentatively identified as William M. “Billy” Gore, his wife Gleneria Gore, and her son, 17-year-old Anthony Basco, said Grant Parish sheriff’s lead investigator Jody Bullock.

Investigators believe the other victims include a 13-year-old child of Gleneria Gore’s, a 13-year-old friend sleeping over and a 9-year-old child of the couple’s. Genders for the three weren’t released.

Investigators were waiting on positive identification of all the victims from the Jefferson Forensic Center.

The home had a history of electrical problems and that could have caused the fire, investigators said. They were unable to describe the cause more specifically because of damage.

“It’s just hard, upsetting. I am just wondering how it happened. I guess it would be easier if I knew they didn’t suffer, because I think about those little kids,” Johnnie Harris, 38, a longtime friend of the house’s residents, told the Alexandria Daily Town Talk.