The Basque separatist group ETA set off a series of bombs across Spain Monday, but no one was seriously injured in the resurgence of violence by the outlawed guerrillas, Spanish officials and media said. 

The small bombs -- the second major ETA attack since Friday -- exploded simultaneously in cities up and down the country after ETA had called in warnings to a Basque newspaper.

Ten people suffered hearing problems from a blast in Santillana del Mar, on Spain's northern coast, and one person experienced similar problems from the bomb in Ciudad Real south of Madrid, government officials said.

There were other explosions in Valladolid, Leon, Avila. Spanish media also reported blasts in Malaga and Alicante on the southern coast.

ETA, fighting for an independent Basque state in northern Spain and southwestern France, on Friday detonated five bombs simultaneously at service stations along major highways around Madrid, slightly wounding two police officers.

The attacks mark a show of strength by ETA after months of relative inactivity and a police crackdown that had hit the group hard.

Spanish and French police have arrested more than 100 ETA suspects, including the top leadership in a raid in France two months ago that rounded up 20 suspects and a major arms cache in the harshest blow against ETA in 12 years.

Yesterday was a public holiday in Spain to celebrate the 1978 constitution, bitterly opposed by ETA for enshrining the Basque region as part of Spain. Police had warned of a possible ETA attack.

"ETA knows it only has one destiny and that is the end of violence and leaving arms behind. ETA knows the rule of law, which is what democracy is, has been and will be stronger than any attempt to change the rules through violence," Prime Minister Jose Luis Rodriguez Zapatero told reporters when asked about the ETA threats yesterday.

The group has killed nearly 850 people since 1968 in a bombing and shooting campaign for an independent Basque state.

But until Friday it had been relatively inactive since the March 11 train bombings by Islamic militants, which the then government at first erroneously blamed on ETA.

The bombs, some hidden in places like garbage containers, have dashed hopes of Christmas truce after the guerrillas and their closest political allies called for peace talks with the government -- offers rejected by the mainstream political class.

None of yesterday's blasts were within Spain's Basque Country, which is made up of three provinces in the north of Spain that Basque nationalists say are part of a greater Basque homeland including Navarra and three provinces in France.

(China Daily December 7, 2004)