Michael Figueroa, 26, told the woman he was a detective when he entered her Clinton Avenue home around midnight Sunday, authorities said.
He had handcuffs, a holster and a block rod on his hip, the ABC7 report says.
"The fire department of Mount Vernon operates with the highest integrity," the Mount Vernon fire commissioner said in a statement. "We are reviewing the incident in question. We will follow the established process and will take appropriate disciplinary action, if warranted."
Police charged Figueroa with criminal impersonation and released him on $750 bail pending court action.
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