Passengers watched in horror as a train pinned a man to a railway platform as he tried to cross the tracks at a station.
The man was seen walking calmly across the line with shopping bags in his hands at Portslade Station.
He had reached the other side and was trying to haul himself up onto the other platform when a train heading towards Southwick left the station and crushed him.
Onlookers said they feared the man would have been killed if the train driver had not stopped so suddenly.
Paramedics and firefighters from Lewes, Preston Circus and Hove took about 20 minutes to free the man who was semi-conscious and in great pain throughout the rescue, shortly before 3pm on Saturday (February 16).
The man, who is believed to be 32 and from Brighton, is said to have suffered life-threatening injuries. He was in Royal Sussex County Hospital last night (February 18).
Southern reported that services were disrupted between Shoreham and Brighton for up to an hour following the incident.
A friend of the man contacted The Argus to say the victim had been sedated on Saturday and was suffering from a broken pelvis and internal bleeding.
He said: “I had just dropped him off from the pub to the station when I saw on Facebook someone saying that a man wearing a white tracksuit had been hit on the train line.
“I have no idea why he was on the track. He must have been crossing to get to the other side.”
EDF employee Marcus Webber, from Brighton, saw the man walk across the tracks.
He added: “The Southwick train started moving and he started screaming.
“I was at the crossing with other people including some kids and when he got trapped they screamed.
“I remember seeing the doors close and the train being ready to go before he walked in front of it.
“There is an underpass at the station so there was no reason for him to do it.”
Allan Jempson, 58, from the Knoll estate in Hove, said: “He got to the front of the train, right in the blind spot of the driver, and then the train started to pull out and everybody was just shouting and screaming at the driver to stop.
“He got rolled a couple of times but luckily the driver stopped just in time.
“If he had picked up more speed, the man would have been a goner.
“The guy was completely oblivious to it all.”
Watch commander Stuart Black, from Hove fire station, said: “He was semi-conscious and in a lot of pain throughout and has suffered serious injuries.
“He was trapped between the side of the train and the platform edge by his chest.”
Labour Portslade councillor Bob Carden said: “I cannot believe that anybody would do something like that but well done to the emergency services for getting him out.
“I wish the guy well and hope he recovers but it’s the driver and staff I feel sorry for because of the stress of having to deal with something like that.”
A Southern spokeswoman said: “Crossing live railway tracks at any time is extremely dangerous.
“Passengers should always use designated underpasses and footbridges at stations when crossing from one platform to another.”
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