MADRID, Oct 8, 2008 (AFP) - Spain has boosted security across the country ahead of its national day on Sunday because of the threat of an attack by Basque separatist group ETA, a top interior ministry official said Wednesday.

Spain has also stepped patrols along its border with France, which has traditionally been used as a rear base by the separatist group, in cooperation with French authorities, said secretary of state for security, Antonio Camacho.

'What we are doing is avoiding and preventing attacks and guaranteeing the security of our citizens,' he told reproters, adding ETA has carried out several attacks in recent weeks and 'its intention is to continue carrying them out'.

ETA is blamed for 824 deaths in its 40-year campaign of bombings and shootings for an independent Basque homeland, with police and government officials a prime target.

The outfit's last victim killed when a car bomb exploded outside a military school in the northern Cantabria region, which is near the Basque region, on September 22.

The attack was one of three in northern Spain that weekend blamed on ETA and in which 11 people were also wounded.

A bomb exploded Saturday outside a courthouse in the Basque town of Tolosa, causing extensive damage but no injuries.

French authorities on Wednesday extradited to Spain a suspected ETA member who was arrested in France in 2001 following a shootout with police, the Spanish interior ministry said.

Inaki Lizundia Alvarez, 30, is a member of ETA's 'information structure' and is wanted for 'cooperation with an armed group', the ministry said in a statement.

Alvarez had previously been sentenced by a Spabish court to an 18-month jail term for assualting a police officer in the Basque city of Bilbao in 1993.