The most recent attack happened Tuesday night at 4:40 p.m. near Franklin Avenue and Fulton Street.
Investigators said the 42-year-old victim was approached by the suspect who took the victim to an alley where he produced a firearm, struck her in the head, and then sexually assaulted the victim.
The victim described the attacker as a black man, 25 to 35 years old, 5'8"-5'11", 160-180 lbs. He was wearing a green jacket, dark pants and white sneakers.
The same suspect is believed responsible for attacking a 56-year-old woman a week earlier.
It happened at 1:00 in the morning on March 16th, also in the vicinity of Fulton Street and Franklin Avenue.
The suspect had a gun, forced the victim to John Hancock Park where he sexually assaulted her and struck her on the head with the firearm causing a laceration. The suspect then fled the location on foot.
The victim in that case said the suspect had short black hair and brown eyes. He was wearing a green baseball hat, a green military jacket, black boots and brown jeans.
Anyone with information is asked to call Crime Stoppers at (800) 577-TIPS (8477).