The sexual assault happened on Sept. 29 just before 3 p.m. on E Street and W. 4th Street, Boston police said.
On Oct. 4, he followed a woman out of a convenience store around 8:30 p.m. to 506 E 6th St., where he pulled out a knife, punched her in the face, and then ran away.
Boston police ask anyone with information on who he is to contact Area C-6 detectives at 617-343-4742. Anonymous tips can be left by calling CrimeStoppers at 800-494-TIPS or texting the word 'TIP' to 27463.
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