SAN FRANCISCO (CBS/AP) –San Francisco’s public transit agency is coming under fire for overtime costs.

The city’s Municipal Transportation Agency is on pace to break its overtime budget by $18 million this year, a 55 percent cost overrun.

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Some city supervisors have said the agency’s overtime expenses are out of control. Board of Supervisors President David Chiu said he isn’t convinced Muni officials are taking the issue seriously enough.

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Muni officials said they have no choice but to pay overtime given the number of operators the system is down on any given day. The only alternative would be to cut back service.

Although overtime spending is higher than expected, officials said it will not exceed the agency’s overall staffing budget for the year.

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