SAN JOSE, Calif. (KGO) -- A San Jose warehouse that once housed boxing matches in the early 1900s has been destroyed in a fire.
Now, claims of negligence have surfaced about why it may have gone up in flames in the first place.
It's one of two buildings involved in the fire near the corner of Autumn Street and St. John Street and right behind the SAP Center.
The second building's structure is still standing, though it took on serious damage to one side.
San Jose firefighters arrived around 3:30 a.m. Thursday and found a building fully engulfed in flames, collapsing.
"You could actually see the structural members as we pulled up and it had already started to collapse so nobody went inside," Robert Herrera, a San Jose Fire Battalion Chief said.
Firefighters then went into defensive mode, working to save what they could from the vacant building next door.
"There was significant exposure issues with the building that was on fire so the wall on the backside of this building was completely missing and open and crews used aerial master streams and what are called blitz nozzles to flow a lot of water on it to try to get the fire knocked down," Herrera said.
No one was injured in the fire and the cause is still under investigation.
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Fire officials say both buildings were slated to be demolished by the end of the month.
ABC7 learned the land was going to be turned into a parking lot.
"To see this gone now, it really is, I don't think the city or even this valley realizes what the loss is," Carole Rast, a former neighbor said.
Now just a pile of burning debris, the warehouse was considered to be the heart of San Jose's sports culture - Forman's Arena.
"Forman's Arena was where Joe Louis fought and they had skylights at the top of the building where the kids in the neighborhood used to climb up on the roof and they would peer down into those skylights to see the boxing matches," Rast said.
"This was essentially the SAP Center before the SAP Center," Preservation Action Council of San Jose exec. director Ben Leech said. "It was for fight nights for boxing and wrestling, which was the sport at the time."
Leech noted that some parts were supposed to be salvaged for reuse before demolition, including a historic arena sign, which they believe spelled out the word "wrestling."
"We believe that there's something important about having the tangible, visible layers of history," Leech said. "So I look at this and see the smoldering ruins of potential."
Leech had gone to the city with concerns over neglect of the city-owned property, including a failure to secure it.
He says the fire falls on leaders.
"I can't say they wanted this to happen, but they knew this was going to happen," Leech said. "This was a pattern. There was a 100-year-old building that burned down a few months ago, there was a garage that burned down a few months before that. So, this was a known ticking time bomb."
Mayor Matt Mahan says he shares in the frustration.
While the cause of the fire remains under investigation, Mahan believes this is another unsafe situation brought on by failures to address unsheltered homelessness.
He recently saw for himself the risks posed by the unsecured building.
"The interior of that warehouse was full of trash and it appeared people were living inside," Mahan said." And then we had an individual come out in a very threatening manor, who was clearly living in a portion of the warehouse. This is why we have to get everyone indoors."