An explosion apparently caused by a bomb hit a Civil Guard police barracks in northern Spain yesterday, causing damage but no injuries, officials said. The blast, at 7 h 15 a.m. (06 h 15 GMT), damaged the outside of the barracks in the small town of Luna. “There are no injuries but there is some damage to the facade and broken windows at the barracks and some houses.”

There was no claim of responsibility, but a statement from Basque separatist guerrillas ETA in November said the group would continue its violent campaign and warned civilians to stay away from military barracks. The blast came hours after Prime Minister Jose Luis Rodriguez Zapatero said Spain would activate a special security plan to guard against any attacks over Christmas.

ETA, branded a terrorist group by Spain, the European Union and the United States, has killed more than 800 people since 1968 in a bombing and shooting campaign for an independent Basque homeland in northern Spain and southwestern France.

The group has been weakened by more than 100 arrests in Spain and France this year, but recent weeks have seen a resurgence in violence after months of relative quiet.