Richardson Police say a call came in around 8:25 a.m. about a DART bus that had collided with another vehicle.
The crash is located at Spring Valley and Sherman Roads in Richardson.
DART officials say a green SUV traveling northbound on Sherman turned onto Spring Valley, crossed four lanes of traffic and hit the bus as the bus was trying to turn into the DART station.
Ambulances have been dispatched to the scene to transport four passengers to area hospitals.
The driver of the bus was not injured.
DART's police force is taking over the investigation from Richardson PD.