San Antonio, TX – A natural gas explosion at a South Side hotel on Friday morning severely burned two people.

Firefighters responded around 4:20 a.m. to the fire at the Ever-Kleen Motel in the 1300 block of Roosevelt Avenue, where they discovered one of the units totally engulfed in flames.

The fire was eventually extinguished, but two victims were badly burned. A woman suffered first and second degree burns to 75 percent of her body, and a man suffered first and second degree burns over his body as well, officials said. Both were transported to San Antonio Military Medical Center in serious condition.

Joe Arrington, a spokesman for the San Antonio Fire Department, said first responders found evidence on scene that initially led officials to believe the couple had been cooking methamphetamine in the room. Arson investigators have since been able to rule that out and pin the fire to an accident involving natural gas.

Four units at the motel were heavily damaged in the fire, according to the San Antonio Fire Department.