Tommy Robinson will not be charged over an alleged assault at St Pancras railway stations last month.
The Crown Prosecution Service concluded ‘there was not a realistic prospect of conviction’, British Transport Police said.
It comes after the 42-year-old was arrested at Luton Airport on suspicion of grievous bodily harm in connection with an incident at St Pancras station earlier this month.
The police force previously launched an probe after reports a man was assaulted at the busy London railway station on July 28.
Robinson had gone to Tenerife a day later and was wanted for questioning after video emerged of him walking away from the scene.
The 42-year-old, whose real name is Stephen Yaxley-Lennon, was taken into custody by officers after a plane he boarded in Faro, Portugal, landed in Britain.
The CPS have now decided Robinson will not be charged after concluding ‘that [their] legal test for prosecution has not been met.’
A British Transport Police spokesperson said: ‘Following a report of an assault at St Pancras station on 28 July, detectives from BTP quickly launched a full and thorough investigation, which involved a 42-year-old man being arrested on suspicion of GBH at Luton Airport on 4 August.
‘Officers worked at pace to gather evidence, including CCTV footage and witness statements, however the victim did not wish to provide a statement to the investigation.
‘We presented presented a file of evidence to the Crown Prosecution Service (CPS) – who are responsible for considering the evidence available and deciding whether it meets the legal threshold to charge someone with an offence.
‘Following a review of the available evidence, the CPS concluded that there was not a realistic prospect of conviction and therefore there would be no criminal charges in this case.’
A Crown Prosecution Service spokesperson said: ‘We received a file of evidence from British Transport Police in relation to an allegation of assault at St Pancras Railway station on 28 July.
‘Following a careful review of the evidence provided, we have concluded that our legal test for prosecution has not been met.
‘We have informed all parties involved of the decision.’
This is a breaking news story. Live updates to follow.


