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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As Brendan Rodgers departs, Liverpool will be looking for a man with a proven track record, not just a promising future, writes Chris Hall.
When the news of Brendan Rodgers' departure broke at 6.30pm on Sunday night, Twitter was soon awash with reaction.
Brendan Rodgers has been sacked by Liverpool after the 1-1 Merseyside derby draw with Everton