BILBAO (AFP) -- The Basque separatist group ETA, under pressure after the arrests of its top leaders in 2008, ended the year by bombing the headquarters of the regional broadcasting network, police said.

There were no casualties as police had evacuated the area minutes before the blast after a person claiming to represent ETA called the local fire service warning of an imminent explosion at the site, a police spokesman said.
He said the powerful car-bomb exploded at 11:05 am Wednesday, shattering the windows of the Basque Radio and Television (EiTB) headquarters in the Basque economic capital of Bilbao, in northern Spain, and sparking a fire which spread to parked cars.
Smoke poured from the damaged building, which also houses other media groups.
The van that exploded had been stolen earlier in the day and packed with around 100 kilograms (220 pounds) of explosives. The owner was found tied up some distance away in the mountains.
Media groups have frequently been targets of ETA, which is blamed for the deaths of 825 people in its 40-year campaign for an independent Basque homeland comprising parts of northern Spain and southwestern France.
Both the European Union and the United States consider it a terrorist group.
ETA has habitually staged attacks at the end of the year, most recently on December 30, 2006, when it bombed a car park at Madrid airport, killing two Ecuadoran men who were sleeping in their cars.
That attack torpedoed tentative peace talks with the Socialist government Prime Minister Jose Luis Rodriguez Zapatero. ETA then formally called off a 15-month-old ceasefire in June, 2007.
Zapatero condemned Wednesday's bombing, saying ""ETA can stage attacks, but it will lose all the battles.""
ETA is blamed for the deaths of four people this year, including a municipal councilor killed two days before general elections in March and a Basque businessman who was gunned down in the street early this month.
But it has been hard hit this year by police operations in both Spain and France.
The group's presumed overall leader, Javier Lopez Pena, was arrested in the French city of Bordeaux in May in an operation Spanish officials at the time boasted had ""decapitated"" the organization.
In November, French police arrested Miguel de Garikoitz Aspiazu Rubina, known as ""Txeroki"", suspected of being the head of ETA's military operations.
And on December 8, Txeroki's suspected successor, Aitzol Iriondo Yarza, was detained in southwestern France.
France and Spain have stepped up cooperation to crack down on ETA since a special accord was signed in January allowing Spanish agents to operate in southwestern France.
""After all the blows it has suffered this year,"" Wednesday's attack ""is a way of saying 'we are still here,'"" said one Basque analyst, Gorka Landaburu, the director of the weekly newspaper Cambio 16.
He said the attack was likely aimed at moderate Basque nationalists, who support greater autonomy for the Basque region but not full independence.
""The Basque television ... is linked to the Basque government and the (moderate) Basque Nationalist Party, which has governed the region for the past 25 years.