Police said the suspect has robbed at least three people in Harlem after following them into their buildings.
The man threatened the victims with a red-handled hammer, stole their cash and then took off, police said.
Police released a photo of the suspect, who they described as a black man in his 40s who's about 6 feet tall and weighs about 220 pounds.
Anyone with information in regards to the above incident is asked to call Crime Stoppers at 1-800-577-TIPS (8477). The public can also submit tips by logging onto the Crime Stoppers website at WWW.NYPDCRIMESTOPPERS.COM or by texting their tips to 274637 (CRIMES) then enter TIP577.
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