A maintenance supervisor was nabbed for sparking a massive blaze in Queens that injured almost two dozen firefighters, authorities said.

Victor Hidalgo, 49, of Flushing, was illegally operating a propane torch on the roof of a seven-floor apartment building on Bell Boulevard near 215th Street in Bayside just before 3 p.m. Wednesday when the blaze erupted, officials said.

Firefighters battled the flames for more than two hours, leaving 21 with minor injuries.

Hidalgo was charged with reckless endangerment.