PITTSBURGH - A western Pennsylvania man who acknowledged producing child pornography faces a minimum of 15 years in prison when he's sentenced early next year.

Fifty-seven-year-old John Longo of Jeannette pleaded guilty Thursday to one charge of producing material depicting the sexual exploitation of a minor.

Authorities say the retired Pennsylvania Turnpike worker asked a coworker to take sexually explicit images of a 12-year-old girl and email them to him.

Prosecutors say Lisa Renze of Uniontown sent him the pictures between June 2009 and November 2010. She pleaded guilty in April to producing child pornography.

Longo is being detained pending his Jan. 22 sentencing in federal court in Pittsburgh.