LOS ANGELES (AP) — An audit concludes that Los Angeles failed to bill organizers of special events $1.8 million in overtime the city ran up for handling traffic control.

The report released Wednesday by City Controller Ron Galperin blames sloppy accounting and inadequate monitoring.

LA Department of Transportation employees are paid time-and-a-half when they work overtime at special events.

The city picks up the cost for public rallies but organizers of private events such as concerts and movie premieres are expected to pay.

Galperin’s audit shows the city collected $3.5 million for the 2013-2014 fiscal year but should have received another $1.8 million.

Transportation department General Manager Seleta Reynolds says the audit’s findings will be incorporated into departmental procedures.

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