There were no injuries reported in the blaze at 172 Saw Mill River Road in Elmsford Road, according to Greenburgh Police Chief Chris McNerney. The building is across from Casa Building Products.
Greenburgh Town Supervisor Paul Feiner said the building "was the subject of many Building Code violations several years ago.
The Building Department has condemned the building, Feiner said.
The town is assisting 18 people with emergency shelter at the Theodore Young Community Center, Feiner said.
The CERT team and the American Red Cross are assisting.
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