Police are investigating two recent incidents in which a woman was approached and sexually assaulted by a stranger near the downtown Palo Alto Transit Station, one of which took place on Wednesday night.

In both the March 8 incident and the one that occurred on March 1, a person approached a woman near the transit station and grabbed her before being chased away by the victim. Neither woman was injured, according to the police.

The Wednesday incident occurred at about 9 p.m. in the 200 block of Alma Street, police said. A woman in her 20s had just gotten off the bus at the downtown transit station and was walking northbound on the east side of Alma Street when she noticed a man walking about 15 feet behind her, according to a Palo Alto Police Department news release.

When she reached the 200 block of Alma, the man allegedly ran up to her from behind and grabbed her crotch over her clothing, police said. After she screamed, the man let go and ran away southbound on Alma. Police said the woman chased him on foot and followed him eastbound on Everett Avenue and southbound on High Street before losing sight of him. She then called the police.

The woman described the assailant as a "light-skinned" male of unknown race. He appeared to be in his 40s, about 5 feet 8 inches tall and with a medium build. She said he was wearing a green jacket with dark loose-fitting pants and possibly a beanie.

Palo Alto police located a surveillance camera that captured the the suspect a few minutes after the incident occurred.

Police say it's not yet clear whether the alleged sexual battery is related to a similar incident that took place a week prior. On March 1, a woman waiting for a bus in downtown Palo Alto reportedly fought off a man who approached her and sexually assaulted her, San Mateo County Sheriff's Office officials said.

In that case, the victim was waiting for a Stanford Marguerite bus at a kiosk on the southbound platform of the University Avenue Caltrain station at about 11:10 p.m. when a man approached her. According to a news release from the San Mateo County Sheriff's Office, the man began talking to the woman and, while doing so, sexually assaulted her.

After the woman pushed herself away from the man, he allegedly grabbed her to keep her from leaving, according to the news release. She then fought off the suspect, who ran away toward University Avenue. The woman was not injured, according to the news release.

She described her assailant as a Hispanic man, about 35 to 40 years old, between 5 foot 6 inches and 5 foot 8 inches in height and weighing between 190 and 210 pounds. The man was reportedly carrying a black backpack and wearing a green hooded sweatshirt with yellow writing on it, light brown or beige pants and dark tennis shoes. Police said he had short hair and a full beard that was trimmed.

Anyone with information about the March 8 incident is asked to call the Palo Alto Police Department's 24-hour dispatch center at 650-329-2413. Anonymous tips can be e-mailed to paloalto@tipnow.org or sent via text message or voice mail to 650-383-8984. Tips can also be submitted anonymously through the department's free mobile app, downloadable at www.bit.ly/PAPD-AppStore or www.bit.ly/PAPD-GooglePlay.

The Sheriff's Office is also asking anyone with information about the March 1 case to call Detective Mike Baron at (650) 622-8053 or email him at Mbaron@smcgov.org. Those who wish to remain anonymous can call the Sheriff's Office Anonymous Tip Line at 800-547-2700.