A Garland, Texas, man who claimed “curiosity” led him to possessing child pornography was sentenced to 12 years in federal prison on Wednesday.

US District Judge Ed Kinkeade also sentenced Jeffrey David Mitchell, 54, to 10 years supervised release. According to a statement released by the US Attorney’s Office, the 54-year-old pleaded guilty to one count of transportation of child pornography in August 2015.

Authorities became involved in April 2015 after the National Center for Missing and Exploited Children received a tip involving child porn emailed on Gmail accounts. According to a criminal complaint obtained by The Dallas Morning News, the IP address used to send the illicit images was registered to Mitchell. The email addresses also had references to his name and birth year.

“Mitchell admitted he possessed child pornography and that he sent and received child pornography via his email account,” an August 2015 statement detailed. “He confirmed that he created and used multiple email accounts to trade the child pornography and that images of child pornography were on his desktop computer located in his bedroom.”

The US Attorney’s Office claimed law enforcement unearthed 750 images and 100 videos depicting child pornography from Mitchell’s email accounts and electronics in his home. Some of the images and videos—which included infants and toddlers—were violent in nature. Authorities searched the 54-year-old’s home while his parents were present.

Mitchell told an agent that child porn was a “curiosity” and that it didn’t derive any sexual gratification. He later claimed he was attracted to girls age 10 to 15 but that there “should be” explicit images of children in diapers in his possession, according to the criminal complaint.

The complaint also revealed that the Garland man told police that he never had sexual contact with a child, but, in an email with a child-porn trader, he mentioned having sex with a 10-year-old girl.

Mitchell has been in federal custody since his May 2015 arrest.