The city has seen a rash of robberies near its Caltrain stations since this summer, Agent Dan Ryan said; three robberies have been reported at the California Avenue station and another five at the Palo Alto station on University Avenue.
Eight additional robberies have been reported in other areas of the city since around June 20, Ryan said.
The woman robbed Thursday was walking in the 200 block of Emerson Street, near the downtown Palo Alto station.
She was on her way home from her job in the downtown area around 8:45 p.m. when a man on a small BMX bike approached her, Ryan said.
The woman and man had a brief conversation before the woman continued walking. The man then approached her again, grabbed on to her shirt and snatched her purse.
The robber, described as a man in his 20s, average height and build, wearing blue jeans and a black hooded sweatshirt concealing his face, rode his bike around the corner and was last seen riding east on Hawthorne Avenue, police said.
Minutes later, police detained a man matching the description who was in the 200 block of East O'Keefe Street in East Palo Alto, Ryan said. The man allegedly fled from police before officers caught him and booked him into Santa Clara County Jail for resisting arrest.
The man, who has not been confirmed as the robber, was identified as East Palo Alto resident Anthony "Tone" Miller, 30.
Police suspect several groups are responsible for the 16 robberies that have occurred in the last four months and officers have been out in full force to catch the culprits.
Doubling patrol units, moving officers off other assignments and into the downtown area, and working with undercover operations and plain clothes officers have been some of the efforts put forth to stop the robberies, according to Ryan.
Meanwhile, people walking in the downtown areas and near the train stations are encouraged to be vigilant in keeping an eye on their surroundings, especially after dark.
"If you see someone suspicious, be sure to call us and we will come out," Ryan said. "We want people to get on the horn and call us right away."
Callers can dial 911 or leave anonymous tips about the robberies at (650) 329-2190.