The father of a seven-year-old boy who died in a steam engine accident at a County Durham museum was driving the vehicle, police have revealed.
Karl Doran, from Darlington, suffered head injuries at Beamish Museum, in Stanley, on Sunday afternoon.
His father Phillip, 41, was taken to hospital suffering from shock but has since been able to speak to police.
Officers are working with the Health and Safety Executive to establish the exact circumstances of the death.
The emergency services were called to the museum just before 15:00 BST. Karl was pronounced dead at the scene.
Det Ch Insp Victoria Fuller said police were treating the death as a "tragic incident".
She added: "We have already spoken to a number of witnesses but need to speak to some key people who may have been on a bus or tram which passed the traction engine around the time of the incident."
Mr Doran and his son were both steam enthusiasts and frequent volunteers at Beamish.
Beamish Museum director Richard Evans said: "We continue to support the joint investigation and offer our deep condolences to Karl's family."
The museum is still open to the public but the steam engine is not in use.