The tractor driver was airlifted to the Royal Cornwall Hospital

The 20-year-old tractor driver from north Devon, was flown by air ambulance to the Royal Cornwall Hospital. His condition is described as stable.

The train driver suffered shock following the accident at about 1400 BST on Tuesday near Quintrell Downs.

There were only minor injuries amongst the passengers on the 1330 Wessex train from Newquay to Par.

The data recorder is similar to a black box in an aircraft Pc Colin Burrell, British Transport Police

The accident happened at Coswarth crossing near St Columb Road.

The crossing is one of several on the line with no barrier.

Traffic on the unclassified road is controlled by warning lights, switched on by an approaching train, and an audible signal.

The operation of the lights and signal will form part of the investigation.

Pc Colin Burrel from the British Transport Police say the crossing has a data recorder which should provide investigators with information.

He said: "The data recorder is similar to a black box in an aircraft.

"That's now been recovered by Network Rail and myself and we'll download it to get the data from it."

Network Rail says it may be some time before the line and the road are reopened.

A crane is being brought in to move the tractor and trailer from the railway line.

It is the third collision on a level crossing on the line this year.