BALTIMORE (AP) — Corrections officials say a breach in protocol led to the accidental release of a murder suspect in Baltimore.

Thirty-year-old Rodriquez Purnell was released Friday from the Maryland Reception, Diagnostic and Classification Center in Baltimore. He was awaiting trial in the 2013 shooting death of 27-year-old Terrance Rheubottom. He also had been convicted of assaulting a corrections worker.

The Maryland Department of Public Safety and Corrections did not notice Purnell was missing until Monday.

The department said in a statement Tuesday that staff members are required to perform multiple checks on inmates before they are released, and that Purnell was released because procedures were not followed according to department policy. The department also said it would conduct an investigation to identify which procedures were not followed.

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