SAN MATEO CO., 5/14/26 — An undercover investigation in San Mateo County led to the arrest of a registered sex offender from Ukiah who allegedly engaged in explicit conversations with someone he believed was a 13-year-old boy, according to the county Sheriff’s Office.
Detectives working with the Silicon Valley Internet Crimes Against Children Task Force conducted the undercover operation in April to identify suspected child predators, the Sheriff’s Office said Wednesday.
During the investigation, 36-year-old Christopher Purtill allegedly engaged in explicit online conversations with an undercover agent in San Mateo County posing as a teenage boy.
The Sheriff’s Office said Purtill is a convicted felon and a registered sex offender. He is also on active parole for “committing lewd or lascivious acts with a child under the age of 14,” authorities said.
On May 7, detectives working with the Ukiah Police Department and the California Department of Corrections and Rehabilitation arrested Purtill near his home in Ukiah, according to the Sheriff’s Office. He was accused of violating parole and booked into the Mendocino County Jail.