Spain says the leader of the Basque separatist group ETA has been captured in northern France.
Ibon Gogeascoechea, 45, was caught along with two other ETA rebels in a joint Spanish-French raid near the village of Cahan in Normandy.
He was wanted for a plot to attack the Guggenheim Museum in Bilbao during a visit by King Juan Carlos in 1997.
Interior Minister Alfredo Perez Rubalcaba said the other two "were part of a commando [unit] ready to enter Spain". They had come to get their final instructions for the mission.
Security forces believe ETA, which wants independence for the Basque country and has killed more than 850 people over the last 41 years, has been severely weakened by hundreds of arrests in recent years.
The BBC reports much of the improvement has been due to better coordination between authorities in Spain and France, which ETA has long used as a hideout.
Four suspected members of Eta were arrested in Portugal and France in January.
Eta called a short-lived truce in 2006, but broke it in December of that year.