BERKELEY (CBS/AP) — Federal authorities are investigating allegations that a UC Berkeley custodial contractor underpaid workers who cleaned up after football games and other sporting events at the university.

The Los Angeles Times reports employees of Performance First Building Services say they often worked 16-hour days, but were denied overtime and only paid $10 an hour.

Under state law, employees must be paid at least 1.5 times their regular pay for overtime.

Performance First Building Services officials didn’t respond to requests for comment.

The investigation launched by the U.S. Department of Labor comes after the state Legislature passed a bill last month requiring UC contractors to pay wages and benefits equal to those of direct employees of UC who perform comparable work. Gov. Jerry Brown has yet to sign the bill.

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