The historic riverboat housed the President Casino until it closed last year. The fire broke out Friday morning in the roof of the riverboat. Workers on the riverboat safely evacuated. It wasn't immediately clear what they were doing on the boat.
The riverboat provided excursions along the Mississippi River from the 1940s through the 1970s, then housed the casino from the 1990s until it closed last summer.
The cause of the fire has not been determined.
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