IONIA, Mich. (WWJ/AP) – An official with the Michigan Department of Corrections says prison investigators were unable to determine who brought bullets into a maximum security facility in December.

Spokesman Chris Gautz says the investigation has been handed off to Michigan State Police, which will try to find DNA and fingerprints on the bullets found Dec. 9 in the Ionia Correctional Facility.

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A corrections officer spotted the three .22-caliber bullets inside a sealed breakfast tray before it was delivered to a prisoner’s cell, according to The Grand Rapids Press.

Gautz says investigators looked at everyone involved in the food process at the prison during the first three months of the investigation.

Bringing contraband into a correctional facility is a felony offense carrying a maximum sentence of five years in prison.

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Food preparation in all Michigan prisons is conducted by the private company Aramark. The Philadelphia-based company’s work has been under scrutiny since it began a $145-million contract with Michigan in December 2013.

At least three dozen Aramark employees have been banned from prisons for violations. Michigan fined the company $200,000 last August and put an independent monitor in place. The company has promised improvements.

Democrats and a liberal advocacy group have called on Gov. Rick Snyder, a Republican, to cancel the Aramark deal, saying problems were inevitable because of high turnover and lower pay for private workers who replaced roughly 370 state employees who lost their jobs in the outsourcing.

The governor has defended the decision to stick with the food vendor, saying the state was on pace to save $14 million a year through privatization. He also absolved Aramark of responsibility for suspected food poisoning and maggot problems.

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