At least four people have died and 35 people have been injured after a train collided with a bus in Mississippi.
The tour bus was pushed 91m (300ft) along the track following the crash in Biloxi.
A total of 43 people were on the bus at the time, and three of those who lost their lives died at the scene.
It is understood the bus had been stuck on the railroad for about five or 10 minutes when the train struck - and although officials are unsure why the bus had stopped, engine failure is a possibility.
Craig Robinson, who witnessed the crash, told the Sun Herald: "My first instinct was to get down there and tell people to get off the bus, but by the time I got there the train had already hit it."
Rescuers have been removing trapped passengers through emergency windows, and at least one person has been taken to hospital by air ambulance.
The tour bus had been travelling from Austin in Texas when it crashed shortly after 2pm (8pm UK time), and it is thought those on board may have been heading to one of Biloxi's eight casinos.
Biloxi's police chief, John Miller, said: "It's a terrible tragedy and I know there's a lot of families that are going to be impacted."
Mayor Andrew Gilich added that it was "a tragic day for the city".
CSX Transportation, which was operating the freight train, said it was travelling from New Orleans to Alabama at the time of the crash - and its train crew was not injured.
A spokesman said the train had three locomotives, and 27 of the 52 cars were loaded.