The incident happened Friday at Saint Sylvester Church on McKinley Avenue in Cypress Hills.
According to the NYPD, the man entered through an unlocked rear window, then took a collection box with an undetermined amount of cash.
He fled the scene in an unknown direction.
Police describe the suspect as a male Hispanic who was last seen wearing a black baseball hat, green shorts, black sneakers, and a black t-shirt.
Anyone with information about the suspect is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
Tips can also be submitted by visiting the CrimeStoppers website or Twitter @NYPDTips.
All calls are kept confidential.
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