NASSAU BAY, Texas (KTRK) -- The massive fire that destroyed 11 condominiums in Nassau Bay started from the balcony of a top floor unit, fire officials said Tuesday.
The fire, which also caused one building of the Bayfront Towers condo complex to collapse Monday afternoon, is being ruled accidental, according to Tony Russo, the fire marshal for the city of 4,000 people that sits along Clear Lake.
The exact cause of the fire is still under investigation.
Meanwhile, firefighters were back at the condo complex on Lakeside Lane on Tuesday morning to finish general cleanup and to turn over the scene to the complex's management.
While it's not immediately known how many residents were impacted by the fire, up to 16 units were heavily damaged, including those considered destroyed.
Still, the fire came as a shock to people living at the 75-unit complex.
"You're sitting right there watching other people watching their house burn to the ground," said Jean Booth, whose condo escaped serious damage.
"It's terrible. It's really bad," said resident Trina Cameron. "One of the units is owned by a 93-year-old who is out of town and they're trying to figure out how to tell her she lost everything."
In the immediate aftermath of the fire, Russo indicated people were inside the units at the time of the incident.
"There were people at home," he said. "This is kind of an older community in this area, so I don't know exactly how many residents were inside the building at the time, but everyone evacuated safely."
Russo said the fire spread quickly due to a few different factors, including the age of the structure. He said the building is mostly made out of wood and doesn't have a sprinkler system. He said it wasn't required when this building was erected.
He adds there were also strong winds from the south that helped the fire spread.
"We had localized collapses on the backside of the building, and obviously, it was due to the fire damage, but also the weight of the water," said Russo. "On a structure like this, that's to be expected."
About 100 firefighters from 14 agencies, including the Nassau Bay Fire Department along with the city's fire marshal's office and police department, helped battle the fire.
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Massive fire that destroyed Nassau Bay condos sparked from top floor balcony, official says