A major fire is ripping through three connected buildings at the site of the former Bethlehem Steel plant — once one of America's largest steel producers.
More than 100 firefighters have been called to the site, which is the size of approximately six city blocks, the Buffalo News reported.
The fire reportedly broke out around 7 a.m., and was still not "under control" as of 10:15, Buffalo Fire Commissioner Garnell Whitfield told media. The site is located in Lackawanna, New York, just south of Buffalo.
The building ignited after a light bulb fell onto some combustibles, one Lackawanna official said.
Employees who work at the site, which is now home to several businesses, reported hearing a number of explosions from inside the building before the roof collapsed, according to the Buffalo News.
Whitfield said much of the building has already collapsed, and several types of materials are burning inside.
Photos posted on social media showed a massive plume of black smoke rising from the site and a heavy presence emergency response.
Lackawanna Police asking residents on Lincoln near Rt 5 to leave their homes. They say the building will come down. pic.twitter.com/jRD5q4m1Qs
— Barbara O'Brien (@bobrienBN) November 9, 2016
Here is a video clip of the large #warehouse fire in #Lackawanna, NY. pic.twitter.com/tZgtK6JorU
— Chris Zak (@zakchris) November 9, 2016
The roof of the old Bethlehem Steel plant has collapsed. @wgrzpic.twitter.com/LhNhyaKJjc
— Nate Benson (@natebenson) November 9, 2016
Shot of #BethlehemSteel just before roof collapsed. Photo credit: Jon Anderson @news4buffalopic.twitter.com/cTqSFR4BNI
— Jenn Schanz (@JennSchanz4) November 9, 2016
SEE ALSO: Why this steel company is bucking the industry's downturn
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