(AP) -- Missouri Gov. Jay Nixon may be the state's top executive. But figures obtained by The Associated Press show he's far from being the state's top-paid employee.

Forty-six of the state's top 50 paychecks were earned by employees of the Department of Mental Health. Most of those employees are physicians at psychiatric institutions. And many of them earned extra money by staffing facilities overnight and on weekends.

Some mental health facilities pay a physician to remain onsite 24-hours a day in case of an emergency. So some doctors literally have earned thousands while they sleep.

The chairmen of the House and Senate budget committees told the AP they were unaware of the department's special pay arrangement for physicians. They plan to question mental health officials about it at future legislative hearings.

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