URBANA - Authorities at the University of Illinois are trying to find out how a convicted sex offender came to be living inside a campus library.

University of Illinois Police Lt. Roy Acree says 21-year-old Eric J. Kaminski, who gave a Champaign address, was discovered early Thursday morning at the Undergraduate Library in Urbana.

Library security believes Kaminski had been living in the library behind movable bookshelves.

Acree says Kaminski had a folding knife with a 3-inch blade and a sex offender registration form in his possession when he was found.

He says Kaminski was convicted of a sex crime in Michigan, and court records show he was arrested by Champaign police and pleaded guilty in June to a felony charge of failure to register as a sex offender.