A Slidell man will spend 25 years in prison after he pleaded guilty Monday to 35 counts of possession of child pornography as well as two counts of production of child pornography, according to Lisa Page, a spokeswoman for St. Tammany Parish District Attorney Warren Montgomery.

Patrick Emerson, 56, offered his plea to ad hoc 22nd Judicial District Judge Elaine DiMiceli, who sentenced him to 25 years on the production counts and 20 years on the possession counts. The sentences will run concurrently.

Emerson will not be eligible for probation, parole or suspension of sentence, Page said.

Emerson came to the attention of investigators with the Attorney General’s Cyber Crime Unit who were looking into peer-to-peer file-sharing networks. When they approached Emerson, he showed them where he kept his child pornography and admitted he had been collecting such pictures for more than 30 years, Page said.

Of the approximately 1,000 images, authorities determined about 350 of them were pornographic and showed children ranging from toddler age to 13 years old, Page said.

Emerson also had taken pictures of a child he knew, which resulted in the production charges, she added.