7 December 2012 Last updated at 07:25 ET

Misson Springs level crossing 'witness' sought by police

An investigation in to the crash which killed Emma Lifsey is ongoing

A tractor driver may hold information about a level crossing crash in which a four-year-old girl suffered fatal injuries, police have said.

Emma Lifsey, from Haxey in North Lincolnshire, was travelling in a car struck by a train on Tuesday.

British Transport Police want to speak to the driver about the crash at the Beech Hill crossing at Misson Springs, near the border with South Yorkshire.

Officers believe he was in the area and may have witnessed the crash.

A 67-year-old woman who was driving the car received serious neck injuries.

She was taken to hospital in Doncaster and remains in a stable condition.

Officers said they would be speaking to her at the earliest opportunity.

Emma was airlifted to Sheffield Children's Hospital, but died in the early hours of Wednesday.

British Transport Police said they were looking at how the car came to be on the track.

The train has been taken to a depot in Doncaster and is due to be forensically examined.