A Lawrence man has been sentenced to prison for trying to solicit sex online from someone he thought was a 14-year-old girl.

It turned out to be an undercover officer with the Platte County, Mo., Cyber Crimes Unit.

Matthew L. Maslak, 25, was sentenced to five years in prison Thursday for using the Internet to entice a child for sexual purposes, according to Platte County prosecutor Eric Zahnd.

“This man thought he was going to have sex with a young girl, which he perversely called ‘lunch time fun,'” Zahnd said in a statement. “Instead, he is going to serve the next several years in prison.”

According to information from Zahnd’s office, a Platte County sheriff’s detective was in an Internet chat room March 16 at 11:42 a.m. posing as a 14-year-old girl. The detective received an unsolicited message from Maslak, and the talk soon turned sexual.

Prosecutors say Maslak drove to Platte County less than two hours after the chat began believing he would engage in oral sex with the “girl.”

Maslak pleaded guilty to child enticement Sept. 22.

In recent years, police and prosecutors have put an emphasis on fighting Internet-related sex crimes against children.

In November 2004, Eric Melgren, the U.S. attorney for Kansas, described people who seek sexual contact with children online as “a new breed of sexual predator.” He said the number of child-pornography cases filed by his office each year tripled between 2000 and 2004, and that one in five children ages 10 to 17 had received an unwanted sexual solicitation online.