A train driver killed in a crash in Bedfordshire passed a red signal moments before the collision, investigators said.
Shaun Burton, 60, died when the East Midlands Railway (EMR) train he was driving hit the back of a stationary train run by the same operator.
The Rail Accident Investigation Branch (RAIB) said in an interim report that Mr Burton’s train proceeded past a red signal near the scene of the crash in Elstow, near Bedford, at 5.15pm on Friday.
It added that “it is not yet possible to say what indication the driver received” from automatic warning system (AWS) equipment fitted to the train.
Some 162 people were injured, 102 of whom needed hospital treatment.
Fifty-three remain in hospital, including eight in a critical condition.
Images from a forward-facing CCTV camera on Mr Burton’s train show a signal near the scene of the crash “was displaying a red aspect as the train approached and then passed it”, the RAIB said.
Preliminary analysis of a data recorder recovered from the wreckage shows it was travelling at 76mph when its brakes were applied nine seconds before the crash.
Its speed had reduced to 49mph when the impact happened.
The RAIB said its full investigation will consider “the actions of those involved and any factors that may have influenced them”.