The man who police said groped a 12-year-old girl at a Stanford Shopping Center market on Sunday afternoon turned himself in to the Palo Alto police two days later after a surveillance photo from the incident went viral on social media.

Rob Richard Chapman, a 47-year-old resident of San Mateo, called the police on Tuesday to inform officers that he planned to surrender. At about 7:30 p.m., Chapman arrived at the police station, where he was interviewed and arrested on four counts of felony lewd and lascivious acts against a child. Detectives are looking at whether he may have been involved in a similar incident earlier this month.

Sunday afternoon's incident at Sigona's Farmers Market. The girl was reportedly shopping with her mother when the man walked up to her and twice brushed his hand against her buttocks. Later, when the girl was in an aisle by herself, the man allegedly walked up to her and groped her buttocks over her clothes. The girl immediately told her mother what happened, but they couldn't find the man. They called the police more than an hour later.

It didn't take long for Palo Alto police to determine the man's identity. A high-quality surveillance photo immediately went up on local news sites and was shared by the department on Monday afternoon various social-media sites, including Facebook, Nextdoor, Nixle and the department's mobile app. Police credit the social-media response with helping them nab the suspect, whose image was shared on Facebook alone more than 10,000 times. His image reached the timelines of 870,000 users, the police department noted, in addition to being further disseminated by local television, print, radio and online media.

By Tuesday morning, detectives had determined the man's identity as a result of tips called in by people who had recognized him from the photo, police said. Detectives obtained a search warrant for Chapman's house in San Mateo, though he turned himself in before the search was executed. Police later served the warrant on Chapman's home.

Now, Palo Alto detectives are working with Burlingame police to see whether he may have been involved in a similar incident that occurred there on April 4. Palo Alto detectives believe he may have committed similar crimes in other jurisdictions.

Anyone with information about this crime or other similar incidents is asked to call the department at 650-329-2413. Anonymous tips can be emailed 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 bit.ly/PAPD-AppStore or bit.ly/PAPD-GooglePlay.

Links to the Palo Alto Police Department's social media accounts are available at PAPDconnect.