Police believe that one man is responsible for all three assaults, but no suspects have been identified and no arrests have been made.
The most recent incident happened at about 1 a.m. Wednesday, when a man entered the 68-year-old woman's apartment on Beaconfield Terrace and sexually assaulted her while she was in bed. The woman was the victim of a similar attack on June 19, when a man entered her apartment at about 3:20 a.m. and sexually assaulted her.
The woman told police she believed the same person assaulted her both times.
That belief was based on the suspect's appearance, Montgomery County police spokeswoman Lucille Baur said.
The other attack occurred on Aug. 21, when an 86-year-old woman was raped at the Churchill Senior Living Center. The center is located at 21000 Father Hurley Blvd., across the street from the Beaconfield Terrace apartment. A man entered the woman's room in the assisted-living complex through an unlocked window sometime before 4:15 a.m., police said.
The woman was in bed at the time of the attack. She was taken to a hospital for treatment of non-life-threatening injuries.
Montgomery County police said investigators have determined that the June and August assaults were committed by the same person, but would not elaborate on what evidence supports that connection. It's likely that the same suspect is also responsible for Wednesday's attack, police said, but that hasn't been confirmed.
The suspect is described as a black man who in his late teens or early 20s, about 5 feet 8 inches to 5 feet 10 inches tall and about 145 pounds. Police said he has a thin build and no facial hair.
He was wearing a dark shirt and dark pants at the time of Wednesday's assault.
Anyone with information about the cases is asked to call the Montgomery County police major crimes division at 240-773-5070. Tipsters who want to remain anonymous can call Crime Solvers at 866-411-TIPS (8477) or 240-773-8477. People can also send a text message by typing "MCPD" plus the message to CRIMES (274637).