The independent MP Eric Joyce has been released on bail tonight after a day of questioning about a late night brawl in the House of Commons bar.
The Falkirk MP, 52, was arrested on suspicion of assault last night and re-arrested while in custody on suspicion of causing actual bodily harm.
Mr Joyce left the Labour Party after headbutting a Tory MP in a Commons bar last year.
ITV News' Lewis Vaughan-Jones reports from outside Belgravia police station in central London:
While he was held, it was announced Mr Joyce has been banned indefinitely from drinking alcohol in any of Parliament's bars.
The MP was released shortly after 7:00pm and told reporters he had not been charged.
Mr Joyce was previously fined by a court and given a three-month ban on entering pubs and bars following the incident in a Commons bar last February, when he punched and head-butted fellow MPs.