A Turlock man found with more than 600 images of child pornography on his computer has pled guilty in federal court to a felony charge of receipt of child pornography.

Charles Albert Risley Jr., 54, entered his guilty plea Monday to the one felony count lodged against him, the Department of Justice reported.

The case against Risley was brought as part of Project Safe Childhood, a nationwide initiative launched in May 2006 by the Department of Justice to combat the growing epidemic of child sexual exploitation and abuse. Risley gained the project’s attention after a Ceres Police Department detective determined he was making files of child pornography available to users of a file-sharing network in July and August of 2012.

Risley admitted in court Monday that between July 20, 2012, and Sept. 1, 2012, he used the Internet to receive more than 600 images of child pornography. Many of the images depicted prepubescent minors, and several depicted violence or sadistic or masochistic conduct, DOJ spokesperson Lauren Horwood said.

Risley had been convicted in Merced County in 1993 for committing lewd acts with a child under the age of 14, and received a six-year prison term for that conviction. In 2002 he was convicted of failing to register as a sex offender in Stanislaus County. Again, in 2004, he was convicted in Stanislaus County for possession of child pornography.

Risley has been in federal custody since Oct. 12, 2012, and he has been ordered detained as a flight risk and danger to the community.

Risley is scheduled to be sentenced on June 10. He faces 15 to 40 years in prison, a $250,000 fine, and a lifetime term of supervised release.