A creep groped a woman on a Brooklyn street this week — and then pummeled her when she tried to fight back, disturbing new video shows. 

The 26-year-old woman was walking at the corner of South 4th Street and Havemeyer Street in Williamsburg around 2:15 a.m. Saturday when a stranger approached from behind and grabbed her buttocks, video released by cops early Tuesday shows. 

When the woman attempted to slap the suspect, he socked her in the face multiple times, the clip shows. 

The suspect then took off. 

He made some type of statement during the assault, but the victim didn’t remember what he said, according to cops.

The victim suffered bruising and swelling on her face, but did not immediately report the incident to police, authorities said. 

The NYPD’s Brooklyn Special Victims Squad is investigating.

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