By Mike DeNardo

PHILADELPHIA (CBS) — The City Controller says his video investigation shows employees in the city mail center collecting thousands in pay for time they never worked.

They were caught on camera.

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A supervisor and an administrative officer in the city’s mail center put in to be paid for time they never worked, says City Controller Alan Butkovitz.

“Their timesheets were a complete farce when we compared them to our video surveillance.”

And Butkovitz says the supervisor certified inflated time cards for all ten mail center employees during his eight-week investigation last December and January.

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During that time, he says, employees were paid $9,400 for time never worked.

Butkovitz says the supervisor and the administrator left their jobs on their own after the investigation. He’s referring the case to the DA for possible criminal charges.

In the meantime, he says the city Revenue Department is working to recover any pay for time not worked. The department is looking to buy punch-card time clocks to keep tighter controls on time worked.

City spokesman Mike Dunn says that since April, the city has installed its own video cameras in the mail center.

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He says that, and other improvements, have led to a 50-percent reduction in overtime costs.