The far-right activist known as Tommy Robinson has been released on bail by police after being arrested on suspicion of grievous bodily harm.
Robinson, 42, was detained on Monday evening at Luton airport after a man was allegedly assaulted at a London railway station a week earlier.
The investigating force, British Transport Police, said on Tuesday that the man they arrested at Luton airport had been bailed pending further inquiries until 2 September.
Robinson, whose real name is Stephen Yaxley-Lennon, was arrested after arriving at Luton airport on a flight from Faro, Portugal.
The incident that led to his arrest and criminal investigation took place on Monday 28 July at St Pancras train station in central London.
Police said they were called at about 8.40pm to reports of an assault. The man alleged to have been assaulted, aged 64, had serious injuries, police said, and needed hospital treatment.
Hours after the incident at St Pancras station, Robinson took a flight out of Britain, landing first in Tenerife, Spain.
Once abroad, Robinson went from Tenerife to Faro before flying back to the UK on Monday where police were waiting for him. Police said the 42-year-old man they arrested had been “wanted for questioning”.
Video from the scene of the alleged assault, showed a 64-year-old man on the ground and Robinson appearing to claim he had acted in self-defence.
The video does not show how the injured man came to be lying motionless on the floor. The man was admitted to hospital with head injuries and was released two days later.
Robinson is a former leader of the English Defence League. The far-right monitoring group Hope Not Hate describes him as the “best-known far-right extremist in Britain”.
Announcing the arrest on Monday, British Transport Police said: “Officers from BTP have tonight (4 August) arrested a 42-year-old man from Bedfordshire in connection to an assault at St Pancras station on 28 July. The arrest took place at Luton airport shortly after 6.30pm, following a notification that the man had boarded an incoming flight from Faro.
“The man had been wanted for questioning after leaving the country to Tenerife in the early hours of 29 July following the incident at St Pancras.”
The normal practice of British police is not to name an arrested suspect until they are charged with a criminal offence.
