After a spike in indecent assaults, Cambridge police Wednesday urged women who frequent Harvard Square to be on the lookout for predators.

A woman Tuesday night told police  she was walking near the intersection of Garden Street and Massachusetts Avenue when a man bumped into her with his shoulder, then grabbed her buttocks, according to police.

The suspect was described as a black man in his mid-20s wearing a white T-shirt, and standing 5 feet 10 inches tall, with short hair and a stocky build.

Since August 26, three other women have reported similar alleged incidents on Garden Street, in Brattle Square and on the 1400 block of Mass. Ave.

Police arrested 47-year-old Ronald Cattouse of Bedford Aug. 30 in connection with the Mass. Ave. incident and charged him with indecent assault and battery and assault and battery with a dangerous weapon. Cattouse grabbed a woman’s breast, then cut another victim’s hand with a pair of scissors, police said.

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There have been other assaults reported outside Harvard Square, police said.

Police arrested 25-year-old Bruce Burke of Cambridge and charged him with assault for slapping a woman’s buttocks Sunday, Aug. 6.

Ronard Byrd, 50, of Quincy, was charged with assault after officers witnessed him “inappropriately touching” a woman sleeping on a bench, police said.

Police in the city were reportedly collaborating with Harvard University officers to investigate the incidents. It was not immediately clear whether any of the alleged attacks are related, police said.

Anyone with information is encouraged to call Cambridge police at 617-349-3300, send an anonymous text to 847411 (begin the text with Tip650) or email police via the Cambridge’s MyPD app.