"People stole a lot and nothing ever happened to them," says lawyer Lola Alonso outside a Spanish court hearing the latest corruption scandal, a scourge that could cost traditional parties dear in upcoming elections.

The 44-year-old has just come out of court in Huelva, a small town in the southern Andalucia region where for weeks a judge has been questioning more than 1,000 people, both defendants and witnesses, in connection with the alleged embezzlement of European funds destined for training the unemployed.

Four suspected members of the Basque separatist organization ETA went on trial in Spain Wednesday accused of planning a missile attack on a plane carrying then prime minister Jose Maria Aznar in 2001.

The four face prison terms of up to 72 years each if convicted of the charges that include "attempted terrorist killings" and "belonging to an armed organization", at Madrid's National Court which handles terrorism cases.

Aragon is to Spain like Ohio is to the United States: for more than 30 years this northeastern region has always voted for the winner of general elections, and this year should prove no exception.

Polls predict a small victory for the ruling Conservative Popular Party (PP) in December 20 elections but without an absolute majority, which would force it to get into bed with another party -- or see others grab power by forming unlikely alliances.

Spanish Prime Minister Mariano Rajoy officially kicked off his campaign for re-election Thursday evening with the promise that his party "takes Spain seriously", ahead of tight legislative polls on 20 December.

The head of the outgoing government faces three challengers who were unknown when he first took power in 2011: rising star Albert Rivera, 36, from the centrist Ciudadanos party, the Socialists' Pedro Sanchez, 43, and far-left Podemos candidate Pablo Iglesias, 37.

A trial of 35 members of Basque separatist parties including Batasuna, the banned political wing of the armed ETA group, got underway Thursday in Spain after being repeatedly postponed.

The defendants stand accused of carrying out political activities to back ETA, blamed for the deaths of 829 people in a four-decade campaign for an independent Basque homeland in northern Spain and southwest France.

Spain's Constitutional Court on Wednesday revoked a resolution passed by Catalonia's parliament that declared the start of a secession process in the wealthy northeastern region, Prime Minister Mariano Rajoy said.

"It was a unanimous decision," the conservative prime minister said during a speech.

Official campaigning for Spain's December 20 general election begins Friday with conservative Prime Minister Mariano Rajoy facing a stiff challenge from three younger rivals in the tightest race in decades.

With some polls showing that more than one in five potential voters are still undecided less than three weeks before the election, it is impossible to predict who will win, said Manuel Mostaza, the operations director at the Sigma Dos polling firm.

Spain's prime minister spurned the country's first pre-election debate of its kind Monday, an empty lectern on stage marking his no-show as other candidates made repeated digs he was unable to defend.

Rising star Albert Rivera from the centrist Ciudadanos party, the Socialists' Pedro Sanchez and left-wing Podemos candidate Pablo Iglesias had sometimes heated exchanges for close to two hours in an unprecedented debate for a country long used to bi-party politics.

Spain's interior ministry said Saturday it had arrested in two men suspected of trying to recruit people for Islamic jihad, or "holy war", as well as a woman ready to go to the conflict zone.

The men of Moroccan origin, aged 32 and 42, were arrested in Barcelona, the ministry said in a statement without specifying the date.

Spain's government is stuck between a rock and a hard place.

Keen to show France support in its battle against extremism, Prime Minister Mariano Rajoy is also acutely aware that any concrete engagement will awaken the ghosts of Spain's devastating 2004 attacks just weeks ahead of general elections, experts say.