The fast, engulfing eight-alarm blaze cost an estimated $1 million in damage, officials said.
Meanwhile, state police said they are continuing their investigation into the commercial structure fire that prompted the evacuation of more than 100 workers and injured one firefighter.
"At this point in the investigation, the cause of the fire is yet to be determined," state police from Troop K said in a news statement released late Wednesday.
Production at Gap's complex -- which includes a 990,000-square-foot warehouse called Building 2 -- halted as a result of Monday night's blaze. the fire was contained about four hours after it broke out by firefighters from 20 fire departments in three counties.
The Alcohol, Tobacco and Firearms (ATF) National Response Team, which has federal jurisdiction over fires involving interstate commerce, is on scene and partnering with the Dutchess County Fire Investigation Division, the New York State Office of Fire Prevention & Control and state police to determine the cause of the fire.
Anyone with information relevant to the investigation is asked to contact state police at their Poughkeepsie barracks by calling 845-677-7300.
Monday's eight-alarm fire broke out on the second floor of the Gap warehouse about 10:45 p.m., authorities said.
One firefighter sustained minor cuts to his lower leg while battling the blaze, which was contained by hundreds of firefighters from Dutchess, Putnam and Orange counties.
Dutchess County Executive Marc Molinaro and several other county and state officials were at the fire scene at 100 Merritt Blvd. in Fishkill.
The entire site, which employs more than 600 people and as many as 1,800 at peak distribution times, was taken "off line" because of the fire, according to Colleen Pillus, a spokeswoman for Dutchess County Executive Marc Molinaro.
The 108 warehouse employees are still being paid by Gap even though they have nowhere to work at this time.
For a previous Daily Voice report on the blaze, click here.
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