The bus, with 16 inmates and 3 correction officers on board, crashed about a mile north of the Spring Valley tolls in Rockland County.
The prisoners were rescued and lined up under guard. Those who were injured on stretchers were also place under guard.
The driver has told investigators he was cut off.
The inmates were being transported from Rikers Island to the Ulster Correctional Facility, a medium security prison.
The overturned bus blocked all three northbound lanes. For nearly two hours the thruway was closed in one direction, bringing traffic to a standstill for miles.
In addition to clearing the accident, the prisoners needed to be secured before the highway could reopen, so state and local police were called to the scene as a precaution.
Eventually all 19 passengers were transported to Good Samaritan Hospital for evaluation.
The prisoners were treated in a separate area with a police or correction officer assigned to each inmate.
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