Tommy Robinson has left the country after a man was knocked unconscious at St Pancras International Station.
The victim - seen lying face down on the concourse - suffered serious injuries and had to be taken to hospital after being given CPR by paramedics at the scene in central London.
Footage shared on social media appeared to show the far-right political activist - real name Stephen-Yaxley Lennon - speaking to witnesses. He could be seen in the video looking agitated and left via an escalator while saying: "You saw him, he came at me."
A British Transport Police spokeswoman said today the suspect in the case flew out of the country in the early hours of this morning.
READ MORE: Tommy Robinson LIVE: Far-right activist seen agitated near 'unconscious man'
They said: “Following a report of an assault at St Pancras station last night (28 July), officers have confirmed that the suspect, a 42-year-old man from Bedfordshire, boarded a flight out of the country in the early hours of this morning.
"Detectives are continuing to work closely to progress the investigation and bring him into custody for questioning.”
An eyewitness to the incident last night said eight police vehicles were lined up outside on both sides of the station after the incident at around 8.40pm.

They told radio station LBC: "I saw an unconscious man being worked on by paramedics – they erected curtains around him. They were trying to resuscitate him and there was what looked like a blood transfusion bag.
"The station was still open as normal while the incident was being dealt with."
A concerned bystander was also heard in the video clip desperately trying to get someone to help the injured man, before paramedics arrived. The eyewitness could be heard saying: "Quick, quick, can we get someone here quick."
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