A car bomb exploded in the northern city of Bilbao in Spain's Basque Country today, burning the bodyguard of a Socialist councillor, police and government officials said.
There was no immediate claim of responsibility, but the regional government blamed ETA Basque rebels.
The attack took place a few days after a judge arrested most of the top leaders of the radical party Batasuna, banned because of links to ETA. The group described the detentions as "a declaration of war".
The bomb in Bilbao's La Pena neighbourhood had been planted underneath the car of a man working as a bodyguard for a councillor from Spain's governing Socialist Party and exploded as he started it at about 9:35am (local time), officials said.
Investigators believed the bomb may have contained ammonia, although it was too early to rule out other theories, Spain's Security Secretary Antonio Camacho said.
Mobile phone video footage shot by a witness just after the blast showed the Renault car in flames. The blaze also engulfed another vehicle parked next to it.
It was not known whether the bodyguard or the councillor for whom he worked was the target of the attack, Camacho said.
The 37-year-old bodyguard was taken to the Hospital de Cruces in Bilbao for treatment. The hospital said he suffered burns on 4 per cent of his body.