Those charged were among more than a hundred arrested by Greek police as part of the investigation into the killing. Photo: AFP
All 40 were remanded in custody, taking the number charged so far to 70.
These new indictments are in addition to the 30 made on Friday, the first day of the investigation into violent clashes which erupted Monday between hardline supporters of Dinamo Zagreb of Croatia and AEK Athens in the Greek capital.
Following his death, UEFA postponed Tuesday's third-round qualifier between the two sides until August 19.
Police made around 100 arrests -- most said to be linked to Dinamo's extremist 'Bad Blue Boys' supporters, a police source said.
Of the 30 charged on Friday, a dozen -- 10 Croatians, an Albanian and a Greek -- were remanded in custody, Greek news agency ANA reported.
On Tuesday, the Greek minister for citizen protection, Yannis Oikonomou, suspended seven police officers, saying they had failed to ensure adequate security measures to prevent the brawl.
The death of Katsouris caused shock in a country that has seen several incidents of violence erupting at football matches.
Last year, teenager Alkis Kampanos was fatally stabbed in a fight in the northern city of Thessaloniki between supporters of the city's rival clubs, Aris Thessaloniki and PAOK.
The government subsequently increased the maximum sentence for fan violence from six months to five years.
Last month, seven defendants were found guilty of Kampanos's murder and handed life terms. Five others were jailed for complicity.
Police meanwhile have beefed up border security in the wake of this week's killing.
Supporters of AEK and Dinamo have been banned from travelling abroad for the clubs' two forthcoming encounters -- the qualifier in Athens on August 19, and the second leg in Zagreb next Tuesday.
On Thursday, seven Romanian fans were arrested on the border between Greece and Bulgaria in possession of two knives.
They were given one-year suspended prison terms on Friday and each fined 1,000 euros ($1,095), a police source reported.
According to police, the supporters were on their way to Thursday's Europa League qualifier between Olympiakos and Belgian side Genk.
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