Investigating judges have begun questioning a dozen people on Friday after the death of a young supporter of the AEK Athens football club. Michalis Katsouris, 29, died of a haemorrhage after being stabbed in the arm in violent incidents on Monday night between ultras from Croatian club Dinamo Zagreb and AEK Athens. 

A hundred Croatian supporters suspected of being linked to the Bad Blue Boys, Dinamo Zagreb's ultra supporters group, as well as two Greeks, an Albanian, a Bosnian and an Austrian were arrested on Tuesday before being prosecuted the next day for homicide and participation in a criminal organization, according to a judicial source.

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Police said between 100 and 120 Dinamo Zagreb fans had showed up late that evening to confront AEK fans. Clashes broke out more than an hour after the visiting team's training session ended and the team had left the stadium, with fans from both sides hurling flares, makeshift explosives and stones, police said.

Three Greek and five Croatian fans were also injured. Dinamo Zagreb condemned Monday's incident, saying that such events were "not in line with the values ​​and ethics we promote as a club and community."

Condemnation

On Friday, the first group of some 30 fans were led in handcuffs from Athens police headquarters to buses set to shuttle them to the capital's main courthouse to answer magistrate questions a over their alleged involvement in a criminal organization, disturbing the peace and bodily harm.

The hearings of the suspects are due to end on Sunday evening, according to media reports. 

The UEFA Champions League qualifying-round match between AEK and Dinamo Zagreb had been scheduled to take place at AEK's stadium on Tuesday, but it has since been postponed to August 19 due to the tragedy.

"Violence has no place in our sport and we expect that those responsible for this terrible act be arrested and consigned to justice in the shortest delay," UEFA said.

The death of Michalis Katsouris has shocked Greece where violence frequently marks football matches. Greek Citizen Protection Minister Yannis Oikonomou suspended seven police officers who have been accused of failing to take adequate measures to prevent the violence in Nea Filadelfia.

Authorities in Croatia and Montenegro said they informed Greek authorities that Dinamo Zagreb fans were likely to be heading to Greece. The police, who have intensified border controls in recent days, arrested seven Romanians on Thursday, suspected supporters of a football club in their country, in possession of two knives.

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