Police in Cambridge issued an alert after a woman said she was the victim of an attempted sexual assault after leaving Porter Square early Wednesday.
The woman had just left the Porter Square MBTA station just after midnight and was walking alone along nearby Richdale Avenue when the attack occurred, police said.
"The victim was able to fend off the attacker and return to safety," Cambridge police said in an alert.
Police said they have a limited description of the suspect: a man wearing all dark clothing.
Police urged people to be aware of their surroundings at all times, to always walk with a friend or in groups if possible, to walk with confidence with a good, steady pace and turn and look at the person if you feel you are being followed.
Authorities are investigating.
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