(CBS) — A visitor to Cook County Jail was trapped in the jail for 30 hours over the weekend and now the sheriff’s office is investigating to find out what went wrong. WBBM’s Steve Miller has the exclusive story.

It happened in the super maximum security Division 9 when Chicago man went to the jail to visit his son.

He went into a visiting room that was not being used, but the door was propped open by contractors installing cameras.

“Unfortunately the door locked behind him,” said Cara Smith, executive director of the Cook County Jail.

She says the man was trapped from about 6 o’clock Saturday evening – until about 1 o’clock Monday morning.

“For approximately 30 hours. A very, very long time by any measure,” said Smith.

Smith says the man pounded on the door, but in a maximum security division the walls and the doors are thick.

Finally, she says, he broke a ceiling sprinkler head and the fire department came. Smith says he had to go to the hospital to get stitches in his thumb.

Now an investigation to see why the door was left propped open and why someone didn’t realize the man never checked out as a jail visitor in the highest security division.

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