SHARECOMMENTMORE

Lake Wales, Florida -- A man, part of an ongoing investigation involving multiple agencies, was arrested Tuesday after numerous child porn files were found on his computers.

Authorities say the investigation into 59-year-old William McCallister began in December 2011 after the Winter Haven Police Department received information hedrugged a woman at his Florida Polygraph Associates, Inc. and sexually battered her during a polygraph exam. In that incident, he was charged with delivery of a controlled substance, extortion and attempted sexual battery.

Then in August 2012 during a search at his Lake Wales home, Polk County detectives found a .357 Smith and Wesson revolver. He was charged with possession on a firearm by a convicted felon.

Most recently, detectives found 31 images of child porn on his home computers and have charged him with 31 counts possession of child porn and violation of pre-trial release conditions.

McCallister's criminal arrest history includes serving 15 years in prison for seven counts of robbery, kidnapping and two counts of administeringbarbituratesin 1992 after the Orange County Sheriff's Office investigated cases where he was suspected of drugging women in bars.

Detectives believe McCallister may have other vicitms who have yet to come forward. Anyone with information about McCallister's crimes is urged to contact the Polk County Sheriff's Office at 863-298-6200.