ETA suspects held in Spain

Spanish police arrested four suspected members of Basque separatist guerilla group ETA on Saturday, two of whom may have been planning an attack on Basque police, the government said.

The four - named as Yosune Ona, 27, Asier Mardones, 24, Atxarte Navarro, 27, and Aritz Lopez, 23 - were detained in the northern Basque region, an Interior Ministry statement said.

Ona and Mardones, who were armed when they were arrested, are believed to be linked to an ETA shootout with police last September, the statement said, adding that they were attempting to reform an ETA cell in the Vizcaya region that police broke up last year.

"It is not ruled out that they may have been preparing some attack on members of the Basque autonomous police force," it added.

ETA, which the United States and European Union consider a terrorist organisation, has killed nearly 850 people since 1968 in a bombing and shooting campaign for an independent Basque state in northern Spain and southwestern France. Last September, members of the Basque regional police force were met with shotgun fire when they responded to reports of a road accident near the northern town of Lagran.

In the ensuing shootout, an ETA guerilla was killed and two police officers wounded, one of them seriously.

ETA later confirmed its members were involved in the shootout but denied the authorities' version of the incident as an attempted ambush.

Experts say ETA has been seriously weakened in recent years by a crackdown by French and Spanish police in which hundreds of ETA suspects have been arrested.

The government of former Prime Minister Jose Maria Aznar initially blamed ETA for the March 11 Madrid train bombings that killed 191 people before evidence emerged that radical Islamists were behind the attacks.

The Socialist government elected three days after the train bombings has maintained a hard line against ETA.