Federal prosecutors say a man already committed as a sexual predator at Larned State Hospital has been charged with making child pornography while in custody.

U.S. Attorney Barry Grissom says 33-year-old Christopher M. Case enticed a 15-year-old and a 13-year-old to videotape sex acts and post them on the Internet while he was a patient in the Sexual Predator Treatment Program. Case also is charged with producing child pornography and sending obscene material to a child.

Case was convicted in 2003 of attempted aggravated indecent solicitation of a child in Saline County.

The hospital is part of the Kansas Department for Aging and Disability Services, which said Thursday the new allegations against Case involved use of a contraband cellphone. The agency says it has taken steps to identify and stop such contraband.