SAN ANTONIO -

A man who was smoking too close to an oxygen tank is believed to have caused a fire that destroyed an entire building -- eight units -- at the Portofino Apartments on the city’s Northwest side.

Even with a steady downpour of rain, San Antonio firefighters were not able to keep the flames from burning through the apartments in the 9400 block of Fredericksburg Road.

Flames were already shooting through the roof of the building when they arrived around 10:30 p.m. Tuesday.

Two people had to be taken to a hospital for treatment of smoke inhalation.

On Wednesday morning, several neighbors, including the Ashleygoodridge family, stopped by the ruins, staring at a huge hole where the building’s roof used to be.

Todd Ashleygoodridge said he heard what sounded like an explosion just as he and his wife were about to go to bed.

“We heard a loud boom and she said, 'What was that? Was that thunder?' I said, 'It didn't sound like thunder,' he said.

His wife, Jacklin, said she quickly rushed outdoors and noticed the flames and heavy smoke, then saw neighbors running for their lives.

“There was a mom and baby out here,” she said. “I brought them a towel and blanket because the baby didn’t have any clothes on.”

"Everybody was out here and just so much anxiety came over me and lot of prayers, instantly," Jacklin Ashleygoodridge said.

According to firefighters, one of the people who lives in the building had been smoking too close to an oxygen tank.

That caused a flash fire which quickly spread throughout the building, fire officials said.

Damage to the building and its contents is estimated at $250,000.

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