CJ de Mooi, a former panellist on the BBC quiz show Eggheads, has been arrested on a European arrest warrant under his real name Joseph Connagh for an alleged killing, Scotland Yard said.
The 46-year-old from Monmouthshire was arrested at Heathrow Airport on Wednesday, according to Metropolitan Police.
The warrant issued in the Netherlands relates to an allegation of murder.
Mr Connagh will appear at Westminster Magistrates' Court on Thursday.
He revealed in his autobiography that he may have killed a man while he lived on the streets two decades ago.
He said he punched a man who approached him with a knife and then threw him into a canal in Amsterdam in 1988.
He wrote in his autobiography: "He caught me on the wrong day and I just snapped."
He added: "I fully suspect I killed him. I've no idea what happened to him."
Mr Connagh, originally from Barnsley, South Yorkshire, became a panellist on the BBC Two show, which features five quiz champions competing as a team against different challengers, in 2003 after winning a series of game shows.
He adopted the name de Mooi when modelling.
Is that a plus or a minus EC 
Eggsactly!
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