Federal authorities say a northwestern Indiana man charged with distributing images of the sexual torture of young children had worked as a substitute teacher in at least three area school districts.

Prosecutors say investigators found 25-year-old Michael T. Wilson of Valparaiso had a child pornography collection of at least 90,000 images and videos. Court documents say FBI agents found that he used a file-sharing Web site to trade the material.

A federal judge ordered him jailed pending a detention hearing on Thursday. A message seeking comment was left Wednesday for defense attorney Clark Holesinger.

A Portage Township schools official says Wilson had worked as a substitute teacher there as recently as last week. He said he knew of no complaints about Wilson and that he'd passed a criminal background check.