Spanish police today arrested two suspected members of the armed Basque separatist group ETA in the city of Valencia and seized explosives.
Police sealed off an area of central Valencia while explosives experts were called in to a hostel where the ETA suspects had been staying, Spanish media said.
Four police vans blocked either end of the street, they said.
"Spanish police have arrested two people in Valencia, a man and a woman, who are suspected members of ETA," Interior Minister Jose Antonio Alonso said.
"They have seized a pistol from them, an undetermined amount of explosives and documents," Mr Alonso told reporters during a visit to Morocco. His remarks were broadcast on Spanish state radio.
Hours before the Valencia operation, a suspected ETA guerrilla was remanded in custody in Madrid for allegedly plotting to shoot Spain's King Juan Carlos.
Another suspected ETA member was ordered to remain in jail pending further investigation for helping the first suspect plot to kill several Basque politicians, a court order said.
In addition, letters seized from the suspects were said to indicate that an ETA leader was eager to kill a uniformed policeman to help lift morale within the outlawed group, which has been severely weakened by a sustained police clampdown.
"We have to start killing people as soon as possible. . . . With the situation we are in, it would be fantastic and give us strength," said the letter, purportedly written by ETA's current leader in France, Garikoitz Aspiazu Rubina, alias "Txeroki" (Cherokee).
ETA has killed more than 800 people since 1968 in a bombing and shooting campaign for an independent Basque state in the north of Spain and southwest of France, but it has not killed anyone since May 2003.
Since then hundreds of ETA suspects have been rounded up in Spain and France.