CHICAGO (CBS) — Managers of the Western Hemisphere’s tallest building are trying to determine how a mentally ill man made it past security and nearly to the top of the building.

Newsradio 780’s Bernie Tafoya reports the man, Brian Woito, of 4600 block of North Sheridan, walked into the building and made it up to the 102 floor before anybody noticed him. Woito’s disheveled appearance went unnoticed by security personnel.

LISTEN: Newsradio 780’s Bernie Tafoya Reports

Somehow security did not notice Woito, who was later seen on security cameras following a Willis employee or tenant into a freight elevator on May 16. He is then seen alone in the elevator randomly pressing buttons. He was in the building for 16 minutes before he was arrested on the 32nd floor.

He was arrested and charged with trespassing.

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