The judge ordered the men to stay in Spain, report to judicial authorities twice a month and declare any change of address.

The men are being investigated on suspicion of providing logistical and financial support to Al-Qaeda in the Islamic Maghreb, or AQIM. The arrests took place Tuesday in the northern Basque and Navarra regions.

Mohamed Talbi, Hakim Anniche, Mounir Aoudache, Abdelghaffour Bensaoula and Ahmed Benchohra have not been charged. National Court Judge Fernando Grande-Marlaska said Saturday that there was no evidence the men had sent "significant sums to Algeria" or that the recipients were "persons related to terrorist activity."

The five men had also been under investigation on suspicion of maintaining contacts with radicals in France, Italy and Switzerland. Police seized a large amount of documents and computer material as part of their probe.

AQIM operates in Algeria and emerged in the 1990s from armed groups fighting the Algerian government after the army stepped in to cancel the 1991 elections in a bid to stave off a victory by an Islamist political party.

The group declared allegiance to Al-Qaeda in 2006, changed its name and renewed a campaign of bombings and kidnappings across the Sahara.

AQIM is currently holding four French hostages, and French officials have called it the biggest terror threat to France and its interests.

Dozens of suspected radical Islamic militants have been arrested in Spain since the Sept. 11, 2001, terror attacks in New York and Washington, and again after the 2004 commuter train bombings in Madrid.

In another development, Spain's conservative opposition People's Party (PP) has extended its lead over the ruling Socialists and is on course to win a parliamentary majority in the Nov. 20 elections, according to an opinion poll on Sunday.

The Sigma Dos poll in the right-leaning El Mundo newspaper gave the PP a rating of 47.4 percent and 31.8 percent for the Socialists, the latter battered by the highest unemployment rate in the European Union and an economy struggling to exit recession.

Prime Minister Jose Luis Rodriguez Zapatero announced in April he would not be seeking a third term.

The PP's lead is now 15.6 points compared to 14.8 points at the beginning of September. The most recent Sigma Dos poll was carried out between Sept. 27 and Sept. 30, on the eve of the Socialists' three-day party political conference in Madrid which ends on Sunday.

PP leader Mariano Rajoy has also sprinted up the polls from a month ago into second place with a rating of 4.39 percent, ahead of Rosa Diez, head of the Union Progreso y Democracia party and Josep Antoni Duran i LLeida, leader in Congress of Spain's second opposition party Convergencia i Unio.

Socialist Alfredo Perez Rubalcaba remains the most popular candidate with a rating of 4.47 percent. He is widely credited with having successfully cracked down on the Basque separatist group ETA during his stint as interior minister.

On Saturday, Spain's banned Ekin organization, a support group for ETA, said it has decided to disband, a move which was welcomed by the government as a step forward in the peace process. ETA announced later it will collaborate with international observers to monitor the ceasefire in the Basque region.