A Spanish court has sentenced a leader of the defunct Basque separatist group ETA to 122 years in prison for ordering the murder of an army officer, judicial sources said.

Known as "Anboto", Maria Soledad Iparraguirre Guenechea arrived in Spain in September after serving seven years in France for theft, extortion and other crimes that bankrolled ETA attacks.

She was handed over on a European warrant in connection with the murder of Luciano Cortizo Alonso who died in a car bomb attack in the northwestern city of Leon in December 1995.

At Wednesday's hearing, the National Court found Anboto guilty of "giving the order and obtaining the explosives for the murder of army commander Luciano Cortizo," according to court documents released today.

The same court had in 1999 convicted Sergio Polo of Cortizo's murder for placing the bomb under his car. In 2015, it reopened the case after finding there was sufficient evidence to prosecute Anboto.

Sergio Polo

Her sentence includes 30 years for the "terrorist assassination of a member of the armed forces" and four 20-year jail terms for "thwarted terrorist murder" of four others wounded in the attack, including Cortizo's daughter.

She was also ordered to pay €92,100 in compensation for the injuries caused and €250,000 for the after-effects of the attack, the court said, denouncing her "brutality and absolute lack of respect for human life".

The court said Anboto, who is now 59, had begun to carry out "tasks with a certain level of responsibility" for ETA in France starting in 1993.

A year later, she began giving "concrete orders to ETA regarding targets that were to be attacked," giving instructions on how to carry out attacks and supplying explosives and weapons. 

Weakened by the arrest of its leaders, ETA announced a permanent ceasefire in 2011 and began surrendering weapons in 2017 before disbanding completely in May 2018. 

During its decades-long campaign for Basque independence in northern Spain and southwestern France, ETA violence killed an estimated 853 people.