Madrid (AFP) - A Spanish High Court judge has opened a preliminary investigation into French Islamist gunman Amedy Coulibaly's stay in Madrid days before last week's Paris attacks, a judicial source said Thursday.
Judge Eloy Velasco will probe the visit by Coulibaly, his partner Hayat Boumeddiene and a "third person who may have helped her reach Syria," the source said.
"The judge has taken this step after receiving a police report," the source added.
The judge will probe the three for the possible crime of cooperation with a terrorist organisation, the source added.
Coulibaly was shot dead by police after he killed four Jewish men in a siege at a kosher supermarket in Paris on January 9.
Earlier on Thursday Barcelona-based daily newspaper La Vanguardia reported Coulibaly was in Madrid between December 30 and January 2 with another person who has not yet been identified.
Spanish authorities are working with their French counterparts to investigate Coulibaly's activities in Spain to determine if there is a support cell in the country with the capacity to carry out attacks.
Spain raised its anti-terrorist security level a notch on January 7, just hours after an attack on the offices of French satirical weekly Charlie Hebdo in Paris that left 12 dead by brothers Cherif and Said Kouachi.
Coulibaly had also shot dead a policewoman in Paris on January 8, the day before he attacked the supermarket.
His partner, 26-year-old Boumeddiene, is known to have been in the Spanish capital before last week's attacks, but this is the first report that Coulibaly himself had been there for three days.
Turkish authorities said Boumeddiene crossed into Syria on January 8 from Turkey after arriving in Istanbul on a flight from Madrid.
According to Spanish authorities some 70 Islamist fighters have gone to conflict zones such as Syria and Iraq from Spain. It is not known how many, if any, have returned.
Interior Minister Jorge Fernandez Diaz said in a recent interview that a dozen more have returned to Spain since the beginning of 2015.
Islamist militants killed 191 people and injured nearly 2,000 in a series of coordinated backpack bomb attacks on trains travelling to the station on March 11, 2004.