The blaze broke out Thursday afternoon in downtown Cohoes, just north of Albany, and was stoked by 20 to 30 mph winds.
The Times Union of Albany reported that three buildings were destroyed, 18 others were damaged and at least 20 people were displaced. The city is under a state of emergency.
"It is the worst disaster the city has ever seen," Mayor Shawn Morse told reporters at an evening news conference.
Morse said John Gomes, of Cohoes, apparently was trying to bend metal in an attempt to imitate the History Channel television series "Forged in Fire" when he started a barrel fire in his backyard that quickly spread. The TV series is about bladesmiths competing to create "history's most iconic edged weapons."
Gomes, 51, was charged with felony reckless endangerment and misdemeanor arson. He pleaded not guilty at his arraignment Thursday night and was jailed on $15,000 bail, the newspaper reported. A preliminary hearing was scheduled for next Tuesday.
Assistant police Chief Tom Ross called the fire unintentional, or "reckless arson."
"We often tell people we don't allow open burns in the city and they often say, 'What's the worst that could happen?'" Morse said. "Well, this open burn just caused millions of dollars of damage and destroyed half our downtown."
The blaze was brought under control about three hours after it began, but an hour later it started back up again. In the end, Morse said, three city blocks had been engulfed in smoke and flames.
A firefighter was taken to a hospital with unspecified injuries, but no other injuries were reported.
Information from: Times Union, http://www.timesunion.com
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