Police on Merseyside have arrested a man wanted in Spain on suspicion of terrorism offences.
The Spanish Interior Ministry said Raul Angel Fuentes Villota, a suspected member of Basque separatist group Eta, had been on the run for 17 years.
He is accused of being involved in several killings in Spain.
Merseyside Police confirmed that a 46-year-old man was being held, and it was in discussions with the Spanish Embassy in London about his extradition.
The Spanish Interior Ministry said Villota, originally from Bilbao, had been living with false documents in the UK and had been, in its words, "waiting for instructions" from Eta.
A statement on the Ministry's website said Villota was recruited in 1990 by a part of Eta known as the Matalaz Command.
'Historic terrorism offences'
He and other alleged Eta members were arrested in June 1991, following a shoot-out.
They were accused of attempting to place a bomb on a police officer's car in the province of Vizcaya - in the Basque region of northern Spain.
Villota was in custody for four years, and released in June 1995.
An arrest warrant was issued by the Spanish central criminal court three months later, after he failed to make a scheduled court appearance.
Villota was arrested on Friday morning in Liverpool, under a European arrest warrant.
A Merseyside Police spokesman said: "Merseyside Police has arrested a 46-year-old Spanish national who was wanted in connection with historic terrorism offences in Spain in 1991.
"Following a period of imprisonment he has since failed to adhere to the conditions of his release, and subsequently a European arrest warrant was issued for his arrest and return to prison.
"He has been detained and Merseyside Police is liaising with the Spanish Embassy in relation to his extradition."