Flames were shooting from the roof of the Southwest Inn, along one of Houston's most heavily traveled expressways, and black smoke was blanketing the area as firefighters tried to extinguish the blaze.
Three firefighters were killed at the scene, while the fourth died at a hospital, according to the mayor's office and local medical examiner. Five other people were injured and were being treated at a hospital for chest pains or leg injuries.
The loss of life is the single worst in the history of the 116-year-old Houston Fire Department. When a flag-draped body was removed from the smoldering remains around 4 p.m., firefighters - working in swirling winds and temperatures exceeding 90 degrees - paused and saluted.
"It's a very sad day for the Houston Fire Department and the city of Houston as a whole," , said Janice Evans, a spokeswoman for Houston Mayor Annise Parker.
Field reports indicate that the firefighters were caught in a roof collapse, said Jeff Caynon, president of the Houston Professional Fire Fighters Association.
"I don't know if that was folks outside next to the structure or inside when it collapsed, but the collapse is going to be the cause," he said after visiting with firefighters at Memorial Hermann Hospital.
Caynon said the victims included three men and one woman. Their names haven't been released.
The blaze broke out just after noon Friday at a restaurant and club at the motel, then quickly spread to the section of the building housing the motel. About 150 firefighters responded and were able to extinguish the blaze within about two hours.
Front desk clerk Martha Lopez told the Houston Chronicle that a restaurant employee ran into the hotel saying a fire had started in the restaurant. The two began knocking on doors and windows telling guests to get out of the hotel. Lopez said the hotel could accommodate 100 guests and had 45 registered at the time of the fire.
Sammy Sewell, who had been staying at the hotel, said he walked out of his room and heard yelling. He said he turned a corner, saw three women screaming and running at him down a hallway. Then, he heard three blasts.
"Next thing you know, it was 'boom!' It scared the crap out of me. I mean, it sounded like a cannon going off. That's how loud it was," Sewell told the newspaper. "I could have sworn it picked this building up and put it back down."