A train driver died at a rail depot when he passed between two trains that were being joined together, investigators say.
The man had just got off a train taken into Tyseley Depot, in Birmingham, at about 20:00 GMT on 14 December and was hit on an adjacent line.
Rail Accident Investigation Branch said it was looking to the circumstances around the death.
No-one else was involved and there was no follow-on disruption to services.
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