The train, travelling from London Paddington, was halted by a herd of cows near Bourne End Railway Station, on Tuesday evening.

Fire crews released one of the cows but the other animal died at the scene.

All 50 passengers were led uninjured to safety and a bus replacement service was put in place, a spokesman for train operator First Great Western said.

The crews did extremely well under difficult circumstances John Bull, fire station manager

The train, the 1945 BST service to Bourne End, was not derailed by the incident but it was damaged and the line was closed until midnight.

Crews from Buckinghamshire Fire and Rescue Service, using ropes, freed the cattle from beneath the train.

Emergency lighting was set up with the assistance of Network Rail and the injured cow restrained while passengers were led to safety by fire crews.

John Bull, station manager at High Wycombe Fire Station, said: "The crews did extremely well under difficult circumstances and we are obviously glad that there were no injuries to passengers or firefighters.