Neighbors of 58-year-old Byron Forester went into his apartment and found him Sunday afternoon after firefighters had gone.
The Dallas Morning News reported Monday that neighbor Clint Risner says he begged firefighters not to leave the first time.
Dallas Fire-Rescue spokesman Jason Evans says firefighters responded to a report of smoke and knocked on the doors of several units. Evans says firefighters left after smelling something like food and thought the odor had gotten into some vents.
Additional 911 calls had firefighters returning. Evans says the resident was dead when firefighters returned.
Authorities are trying to determine what sparked the fire.