PHILADELPHIA (CBS) — A paperwork foul-up in the Philadelphia Prison System allowed a man to go free last month — although he actually showed up for a court hearing Monday in a separate case, only to disappear when a judge questioned why he wasn’t still behind bars.

Now, the Philadelphia Prison System and the pre-trial warrants unit are looking for 21-year-old Shamir Robinson of the 2900 block of Lambert Street in the city’s Nicetown section.

Authorities say Robinson showed up Monday for a hearing on a 2009 robbery case, but when the judge questioned his attorney as to why Robinson wasn’t in custody, court officials say the man simply disappeared from the courtroom.

Prison system spokesman Bob Eskind says a paperwork error going back to June resulted in the mix-up that allowed Robinson to go free last month in a separate 2010 case.

But what’s left, Eskind says, is the unresolved 2009 case for which he should still be in custody.

“We’re hoping that he comes in, that he surrenders himself to the bench warrant unit,” Eskind told KYW Newsradio on Tuesday. “There’s open matters that need to be resolved. He’s charged with robbery and aggravated assault.”

Eskind says the accidental release of Robinson is being reviewed by the system’s Office of Professional Compliance.

Reported by Mark Abrams, KYW Newsradio 1060.

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