Paul Ambler

A 58-year-old San Mateo man arrested in a large-scale online child pornography sweep pleaded no contest to a felony count of possession in return for no more than a year in jail.

Paul Michael Ambler will also have to register as a sex offender for life after his Sept. 5 sentencing. Meanwhile, he remains free from custody on $25,000 bail.

Authorities looked at Ambler after Microsoft received a cyber tip in October 2010 about child pornography being accessed from his IP address, prosecutors said. A search of his home allegedly returned images and videos of children between the ages of 6 and 15 in various sexual acts and some of the pornography came from as far away as the United Kingdom. Authorities reported also finding numerous emails related to trading or forwarding the images, too.

Ambler and nine others — Gordon Lee, 44, of Daly City, Charles Vela Reyes Jr., 46, of Menlo Park, Christopher Daniel Winans, 24, of East Palo Alto, Paul Tazbaz, 36, and Samnang Chun, 23, both of San Mateo, Steve Wilson, 52, and Cruz-Martin Caseiro-Rosas, 32, both of South San Francisco, and Stephen Wolf, 64, of Portola Valley — were arrested in March after being identified as possibly being in possession of child pornography during a Silicon Valley ICAC Task Force investigation headed by the San Jose Police Department. The task force targets peer-to-peer file sharing online by tracking images of pre-pubescent children through individual Internet protocol addresses. The police then searched the homes where those addresses originated.

Lee also settled his case on a single possession count and faces a year when sentenced next week. Chun committed suicide while awaiting trial.