A car bomb exploded outside a police station in Spain's northern Basque region early Sunday, causing major damage and injuring 10 people, hours after another explosion in the regional capital, officials said.

Police blamed armed separatist group ETA, which has been fighting since 1968 for an independent Basque state in northern Spain and western France. The bombings occurred three days after a Spanish court banned a pro-independence Basque political party for having ETA links.

The first car bomb exploded next to the headquarters of the Caja Vital Kutxa bank on the outskirts of the Basque regional capital, Vitoria, a regional Interior Ministry official said. It caused damage, but no one was reported injured.

Several hours later, another car bomb detonated outside a police station in the port town of Ondarroa, according to another regional ministry official. Three police officers and seven civilians were treated for minor injuries, including cuts and ear damage.

Each bomb contained around 100 kilograms (220 pounds) of explosives, the official said.

The second explosion blew large holes in the front wall of the police station. The force of the blast shattered windows in nearby buildings and damaged parked cars. Police examined charred debris that ended up in a river next to the station, an AP reporter at the scene said.

Two suspected bombers parked a vehicle close to the outside wall of the station, threw two Molotov cocktails to attract attention and then detonated the car bomb, the second regional ministry official said.

A person claiming to speak on behalf of ETA phoned in a warning before the first blast, allowing authorities to clear the area, the first official said. No warning was given before the second blast, the other official said.

Both officials spoke on customary condition of anonymity.

On Thursday, Spain's Supreme Court banned the pro-independence Communist Party of the Basque Lands. The move means the government will shut down the party's offices and seize its assets. Nine party members who hold seats in the 75-seat Basque regional parliament will retain them, only stripped of party affiliation.

Earlier last week, the court outlawed another pro-independence party, Basque Nationalist Action, as well as Gestoras Pro Amnistia, an advocacy group for jailed ETA members.

ETA, which has killed more than 825 people in the past four decades, is considered a terrorist group by Spain, the European Union and the U.S.