Louisiana ? A boat carrying state prison employees collided with a barge on the swollen Mississippi River upstream from Baton Rouge on Sunday, injuring 18 people.

The crewboat, with 20 people aboard, was taking workers who had just ended their shifts across the river, said Angie Norwood, spokeswoman for the Louisiana State Penitentiary in Angola. No one went into the water, she said.

The employees were first taken to the prison hospital, and 12 were transferred to other hospitals. The two most seriously injured were flown for treatment, Norwood said.

Normally, the maximum-security prison uses a ferry to take workers and their vehicles back and forth from the west side of the river to the prison on the east side.

But crewboats – typically used to move workers to offshore petroleum platforms – had been used recently because of the high water, Norwood said.