MADRID: Spanish police detained overnight a man who was sentenced to two years in jail for cooperating with the armed Basque separatist group ETA, Spanish media reported Friday.

Police arrested Pedro Maria Olano Zabala in the Basque town of Lizartza in the first detention of the year of someone linked the group, considered a terrorist organisation by both the European Union and the United States, the online edition of daily newspaper El Mundo reported.

They also searched two homes in the town, it added while public radio RNE said Zabala is suspected of transporting explosives for ETA.

Last month the Spanish government warned that ETA may be planning an attack or kidnapping during Spain's six-month presidency of the EU, which began on January 1, and it raised its terrorism level from one to two on a scale of four, indicating a "probable risk of a terrorist attack".

In February the National Audience, Spain's top criminal court, ruled that while Zabala did not belong to ETA he "contributed to its goals" by threatening to kill the mayor of the town, Regina Otaola, who was taken a hard line against Basque separatists.

The court sentenced him to jail for in September 2007 having pointed his finger at the mayor, who belongs to the conservative Popular Party, and said "Otaola, you are going to die!" when she hung the Spanish flag at the town hall over the protests of about 30 people.

Otaola has angered many Basque separatists since she was elected mayor of the town located in a valley just south of the seaside resort of San Sebastian of May of that year with her vocal support of Spanish unity.

Aside from hanging the Spanish flag at the town hall she has removed photos of jailed ETA members, and demanded that all official meetings be conducted in Spanish rather than in the Basque language.

ETA is blamed for 828 deaths in a 41-year campaign for independence in the Basque region of northern Spain and southwestern France.