MADRID (AFP) -- A booby-trapped van exploded in the early hours of Monday in the northern Basque town of Getxo following a warning call from the separatist group ETA, causing no injuries, Spanish media reported.

The bomb exploded on the boardwalk of the affluent seaside town located just outside of Bilbao at 00:50 am causing ""significant"" damage to nearby buildings, public radio RNE reported.
Roughly an hour earlier a man who claimed to speak in the name of ETA called the regional traffic department DYA to warn that a booby-trapped van would explode in the area at that time, it said citing local government officials.
Police then cordoned off the mostly residential area and evacuated homes nearby a suspect van. Police are searching the area for other bombs.
The sound of the blast could be heard several kilometers (miles) away, state television TVE reported.
ETA, whose symbol is a snake wrapped around an axe, has killed more than 820 people in its 40-year campaign of bombings and shootings to carve a Basque homeland out of northern Spain and southwestern France.
The most recent fatality attributed to the group was that of a 41-year-old police officer who was killed on Wednesday when a booby-trapped van exploded without warning outside a police barracks in the Basque village of Legutiano.
Four other police officers were injured in the attack.
Interior Minister Alfredo Perez Rubalcaba said 29 people were inside the police barracks at the time, including five children, and that ETA had intended a massacre.
No one has claimed responsibility for the attack, but police and the government said it bore the hallmarks of ETA.
The group has launched attacks against police barracks in the past and has never phoned in warnings as it does when bombing targets used by civilians.
Interior Minister Alfredo Perez Rubalcaba said 29 people were inside the police barracks at the time, including five children, and that ETA had intended a massacre.
If the attack against the barracks is confirmed to be the work of ETA, it will be the sixth death caused by the outfit since it broke a ceasefire in December 2006 with the bombing of a car park at Madrid's international airport that killed two Ecuadorian men.
ETA announced a ""permanent ceasefire"" in March 2006 but formally called it off in June 2007 citing frustration with the lack of concessions on the part of the government in their tentative peace process.
The group, whose initials stand for Euskadi ta Askatasuna, or Basque Homeland and Freedom in the Basque language, is considered a terrorist organization by the European Union and the United States.
Thousands of people all over Spain staged silent rallies Thursday to protest the killing of a police officer by suspected activists of the militant Basque separatist group ETA. Juan Manuel Pinuel, an officer with the paramilitary Civil Guard, was killed in a car bombing of the barracks where he was stationed in Legutiano in the Basque region.
Deputy Prime Minister Maria Teresa Fernandez de la Vega, Interior Minister Alfredo Perez Rubalcaba and Defense Minister Carme Chacon participated in a rally in the Basque capital Vitoria after attending a funeral mass for Pinuel in the presence of Crown Prince Felipe.
Pinuel was ETA's sixth victim since Prime Minister Jose Luis Rodriguez Zapatero's attempt at a peace process with the group collapsed in December 2006.