CHICAGO (CBS) — An escape at the Cook County Jail on Sunday put the entire building on lockdown and left officers wondering one question: why?

Cook County Sheriff’s spokesman Frank Bilecki said that, just before 11 a.m. Sunday, 20-year-old Jamall Allen of Chicago serving time for residential burglary somehow escaped.

Allen managed to flee from boot camp, a one-year program for non violent offenders, “Eight weeks of which are in a military discipline-type setting. There’s educational programs, anger management, substance abuse counseling, job readiness,” Bilecki said.

LISTEN: WBBM Newsradio’s Michele Fiore reports

Even more confusing was Allen had already served most of his sentence.

“The odd part about this situation, it’s kind of perplexing that this individual … would try something like this, because he was due to be released in 72 days as part of our boot camp,” Bilecki said.

Bilecki said sheriff’s officers located Allen about six hours after his escape. He was within five miles of the jail.

Allen was back in custody Sunday evening and likely facing more jail time tacked on.

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