SLIDELL, La. -- A joint criminal investigation into a potentially illegal boarding house is underway after a man died in a fire Friday morning.

"I walked out my room from up here, came out to big flames shooting out the building," said Cynthia Viering, who also lives at the room-and-board complex on Brownsvillage Road.

While other residents tried to help, Viering said she could only look on in horror knowing someone was still inside.

"They immediately rushed to the aid of the victim," said Jason Gaubert with St. Tammany Fire District #1. "They tried to break the window in an effort to get him out, but because of the amount of smoke and flames, they were unable to do so, unfortunately."

The St. Tammany Coroner's Office identified the man as 63-year-old Bernard Walker. As of Friday afternoon, an autopsy was still underway to determine cause and manner of death.

Fellow residents say Walker had limited mobility and was known to smoke in the room. That's why, for now, firefighters and the St. Tammany Sheriff's Office believe the fire was accidental.

But investigators are also looking into whether anyone was even supposed to be living in the building.

The State Fire Marshal's Office believes the building was constructed and was operating without Fire Marshal approval and contained multiple fire code violations, including no working smoke detectors.

State law requires buildings housing more than four un-related people to be permitted. Investigators say this building contained six rooms.

Now, all three agencies are conducting an extensive, criminal investigation into the matter.

Friday afternoon, other residents affected by the fire were left either receiving relocation help from the Red Cross, or moving in with relatives.

The future of the boarding house operation, as a whole, remains in the air.