'His head flew off': Witness tells of horrific moment man in his 20s was 'decapitated' after looking out of the carriage window and being hit by an oncoming train on the Gatwick Express 

A rail passenger was thought to have been 'decapitated' yesterday after leaning out of a carriage window before being struck by an oncoming train.

The man, who was in his 20s, was on board a Gatwick Express service from the busy airport to London Victoria station when he was struck by a speeding train. 

Police and ambulance crews rushed to Wandsworth Common station in south west London when the man was hit after he 'didn't notice the train was coming'.

One onlooker called Rhianna, from Battersea, said his head 'flew off' and gave Wandsworth Radio a gruesome account of the incident, which was witnessed by two ladies on the platform.

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A rail passenger has died after being struck by a speeding train when he stuck his head out of a window

Police and ambulance crews rushed to Wandsworth Common station in south west London

A private ambulance arrived at the station in London but the man died after he was stuck by a train

She added that there were 15 to 20 people inside the carriage when the oncoming train struck the man on Sunday afternoon.

Rhianna said: 'He lifted his head out and basically he didn't notice that the train was coming, so all you see is basically a head gone.

'The head flew off basically. I actually ran because it was disgusting but all I saw was a head (that) flew away.

'People screamed, the train stopped and people were screaming and they were coming out.

'There was obviously the two ladies, they were more traumatic, but all I saw was a split second of what happened, if you know what I mean.

'I just saw everyone moving, I just had to turn my head away.'

The witness said that there were around '15 to 20' people on the carriage and she recalled the moment she spoke to a woman who was 'traumatised'.

She added: 'The woman that mostly saw it, I spoke to her and she was crying.

'She was just hurt that see saw something like that and she was traumatised.'

British Transport Police are still investigating the incident but added that initial enquiries suggest the man may have been 'leaning out of a train door window' when he 'suffered a blow to the head'.

Police sealed off the area and a number of trains were delayed as authorities dealt with the incident 

A helicopter landed nearby to assist with the operation but the man was pronounced dead at the scene

One Twitter user wrote online that someone had been 'beheaded' by a train in Wandsworth

Social media users were quick to speculate how the horrific incident could have happened on board a train. 

One account, run by a self-proclaimed travel expert known as Mr Sinclair, said the train was 'ancient' and has windows 'easily big enough to put a head through'.

Mr Sinclair wrote on Twitter: 'The class 442 (ancient ones forced by Govt on GatEx) have Windows easily big enough to put head through.

'Many haven't been secured shut. I imagine due to air con poor reliability.'

A separate account, posting under the name Train and Plane Hub, added: 'They (windows) can be opened quite easily and in summer months they're often open for ventilation.' 

Following the devastating incident, several officers carried the man's body - which was wrapped in a blanket - to the back of a private ambulance.  

Officers had placed a police cordon around the entrance to the station after they attended the scene.

The BTP has reported the fatal incident to the Rail Accident Investigation Branch (RAIB) and the tragic death - which is being treated as non suspicious - caused severe disruptions to a number of services in south London. 

Trains had to be diverted or cancelled as emergency services worked at the scene.

The Gatwick Express service between the West Sussex-based airport and London Victoria was disrupted along with many Southern routes including those from Victoria to East Grinstead, Brighton, Bognor Regis, and Hastings. 

The man, who was in his 20s, was pronounced dead at Wandsworth Common in south London on Sunday

Police and ambulance staff rushed to the station (pictured) but the man was pronounced dead

British Transport Police are still investigating but added that initial enquiries suggest the man may have been 'leaning out of a train door window' near Wandsworth Common station (pictured)

A BTP spokesman said: 'We were called at around 5.30pm following a report a man in his 20s had received a serious head injury while travelling on a train between Balham and Wandsworth. 

'Emergency services rushed to the scene but despite their best efforts, nothing could be done to save him. 

'Our investigation remains at an early stage, but initial enquiries suggest the man may have been leaning out of a train door window when he suffered a blow to the head. 

'Officers are currently working to confirm his identity and inform his next of kin.' 

Inspector James Tyrrell, from the British Transport Police, added: 'We are aware of a number of reports on social media which say the man was decapitated, however this is not the case.

'We are continuing to investigate the circumstances of the incident, which has been reported to the Rail Accident Investigation Branch (RAIB), and I'd urge anyone who saw what happened to contact us. 

'The death is not being treated as suspicious and a file will be prepared for the coroner.' 

A London Ambulance spokesman added: 'We were called at 5.34pm to reports of an incident at Wandsworth Common Railway Station.

'We sent an ambulance crew, a single responder in a car and an incident response officer to the scene, alongside London's Air Ambulance.  

'But sadly, despite the efforts of the crews, the patient was pronounced dead by the doctor from the air ambulance.' 

A British Transport Police spokesman continued: 'Medics from the local Ambulance service also attended but the man was pronounced deceased at the scene. 

'A file will be prepared for the Coroner. The train involved was a Gatwick Express Service from Gatwick Airport to London Victoria.'

The man was on board the Gatwick Express (stock photo) from the busy airport to London Victoria

Police and ambulance crews rushed to Wandsworth Common station (pictured) on Sunday afternoon

Southern Rail tweeted that the services between Victoria and Balham would be delayed after the tragic incident 

A spokesman for Gatwick Express, which is run by Southern railway, said it first received reports about the incident at 5.45pm.

He said: 'We have received reports of an incident on board a Gatwick Express train which was en route to Victoria from Gatwick this afternoon.

'The emergency services are in attendance at Wandsworth Common station. We have no further information at this stage.' 

Southern Rail tweeted that services between Victoria and Balham were being delayed, saying: 'Emergency services dealing with an incident between Balham & Wandsworth Common.' 

Residents who live close to the scene said they were shocked to see the air ambulance land on the common earlier in the afternoon.

One said: 'We were coming back across the common when we saw the helicopter land.

'It was at about 6pm. There were lots of police and ambulances there, it was disconcerting.'

Another added: 'I heard a man was hit by a train and heard the air ambulance land on the common. It's such a horrible thing to have happened.'