MADRID (AP) — The riot police officer who died of cardiac arrest during crowd trouble before a Europa League match in Spain collapsed on his own and not in a direct confrontation with fans, authorities said Friday.

Officials in the Basque region of Spain said doctors dismissed the possibility the cardiac arrest was caused by any type of trauma sustained by the officer in fighting that took place before the match between Athletic Bilbao and Russian club Spartak Moscow on Thursday.

There had been conflicting reports about what caused the officer's death, with some saying he might have been involved in a struggle with fans or was hit by one of the many objects being thrown during the altercation.

Five people remained detained — three Russian nationals and two Spaniards — following the violent clashes that took place less than four months before the World Cup is held in Russia.

Authorities identified the victim as 51-year-old Inocencio Alonso Garcia and said he "suddenly felt ill in the course of the serious incidents" that took place outside San Mames Stadium in the northern city of Bilbao.

They said the officer was quickly transported from the scene but went into cardiac arrest before arriving at the nearby Basurto hospital. Doctors said they tried to revive him for more than an hour.

Video footage published by local media appeared to show the moment the officer collapsed while standing near the fighting along with other policemen.

Other images of the clashes showed fans hitting each other, and a group of policemen striking a man on the ground after he fell trying to run away.

"It's hard to understand these things," Real Madrid coach Zinedine Zidane said Friday. "I hope this is the last time we see these types of incidents in a football stadium."

The officer who died was among the large police force summoned to try to keep order as several hundred Russian fans — many of them considered by local authorities as radical ultras — arrived in the city for the round-of-32 match in Europe's second-tier club competition.

The trouble erupted as police were escorting Spartak fans into the stadium and a stray group allegedly started igniting fireworks and throwing flares and objects toward Athletic supporters and police officers.

Police said "violent fans from both clubs" participated in the fighting which spread onto the streets near the stadium located in a central area of Bilbao. Many fans were seen trying to run away from the trouble as fireworks went off all around.

Authorities said they had identified several people before the fighting carrying items that included knives, iron bars, brass knuckles and even bags of stones.

There had been reports of other minor clashes involving Russian fans in Bilbao ahead of Thursday's match, which Spartak won 2-1. Athletic advanced despite the loss, winning the tie 4-3 on aggregate.

UEFA condemned the violent clashes and said it was in contact with local authorities to obtain more information on the incidents, while Spanish league president Javier Tebas called for action by FIFA and UEFA to halt fan violence.

Bilbao will host matches in the 2020 European Championship. Six years ago, a fan died in the city in clashes after a match between Athletic and German club Schalke.

Earlier Thursday, German police arrested a Russian suspected of seriously injuring a British soccer fan during the European Championship in France two years ago.


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