According to a Spanish Interior Ministry statement, Villota, who is originally from Bilbao, has lived with false documents in the UK and has been "waiting for instructions" from Eta.
The Ministry says Villota was recruited in 1990 to join the legal Matalaz Command, under the Command Vizcaya.
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Very cold & icy into Sunday morning across the NW. Snow expected at height over the Pennines, Cumbria and the Lake District -warnings issued
Cold, breezy with wintry showers in places. Snow and ice warnings issued - snow for Cumbria, the Lake District and the Pennines
Merseyside Police will be stepping up their campaign against knife crime this weekend as part of a national week of action.