Police are searching for a man who allegedly raped an 18-year-old woman in a Brooklyn alley on Monday.

The victim was walking in the Bedford-Stuyvesant section of Brooklyn at about 12:40 a.m. when she was approached by the suspect, police said. The suspect showed a hammer and threatened her with it, demanding oral sex.

The suspect then forced the victim to the back alley where he raped her and then fled, according to police.

The victim was taken to Woodhull Hospital.

Police released a sketch of the suspect Thursday. He's described as being in his early 20s, about 5 feet 8 inches and 150 pounds. He was last seen wearing a black Rich Yung-brand cap, a hooded sweatshirt, dark jeans and dark jean jacket. He had on red, white and black sneakers, as well as a black North Face backpack and black frame glasses.

Anyone with information is asked to contact Crime Stoppers at 800-577-TIPS or at nypdcrimestoppers.com.

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