Far-right activist Tommy Robinson has been released on police bail after his arrest in connection with an assault at St Pancras railway station.
British Transport Police did not name Robinson, real name Stephen Yaxley-Lennon, but confirmed a 42-year-old man from Bedfordshire was arrested over an assault in London on 28 July.
The force said the arrest took place at Luton Airport shortly after 18:30 BST on Monday, following a notification that the man had boarded an incoming flight from Faro.
The man was arrested on suspicion of grievous bodily harm and taken into custody for questioning, police said. He was released on police bail until 2 September while inquiries continue.
The statement added he had been wanted for questioning after leaving for Tenerife in the early hours of 29 July following the incident.
Last week, British Transport Police said that a man had "serious but non-life-threatening injuries" following the incident at the railway station in Kings Cross.
The force confirmed later that week that the man had been discharged from hospital.
Video footage on social media emerged shortly after the alleged assault showing Robinson walking back and forth near a motionless man lying on the floor, near the stairs down to the northbound Thameslink line.
The clip did not show how the man ended up on the floor.
Robinson then starts coming back up the stairs, appearing to try to talk to the passing commuter who called for help.
Robinson can be heard saying: "Hes come at me, bruv."
In a video statement posted on X on Tuesday, Robinson said he went to the Spanish island on a pre-booked trip and he told police where he was, as well as his return date.
He also said he was shown the full CCTV footage of the incident in his police interview and called for detectives to share it with the public, saying that it showed he acted in self-defence.
"If someone wants to come up and accost me, confront me and attempt to attack me, Im within my rights to defend myself," he added.
"After seeing the CCTV, I know theres not a jury in the world that would convict me."
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