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CHICAGO — This weekend marks 40 years since the arrest of serial killer John Wayne Gacy.

He quickly confessed and drew a map showing where he hid or buried his victims.

In the days that followed, authorities found 29 bodies in and around Gacy’s home.

Gacy was put to death in 1994. He’s known to have killed 33 people. But the Cook County sheriff’s office calls the investigation “open” as they continue to try to learn the names of victims who remain unidentified.

This is a report from the WGN News archives that aired the day he was arrested in 1978.

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