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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Mainly cloudy today, with strong winds and sustained speeds of 30-35mph, showers later in the day