The crowd chanted anti-fascist slogans as a white coffin carrying the body of the 34-year-old was borne by relatives into a graveyard on a hill overlooking the working-class Athens suburb of Keratsini.
Left-winger Fyssas, who went by the stage name Killah P, was stabbed twice, in the heart and chest, on Tuesday night in a brawl after a football match shown in a café.
His murder has touched a nerve in Greece where austerity has polarised society. Rallies in several cities to mark his death turned violent on Wednesday.
Prime minister Antonis Samaras yesterday called for calm during what he said was an “extremely critical time” for Greece.
“This government is determined to not allow descendants of Nazis to poison society, to commit crimes, to terrorise and to undermine the foundations of a country that gave birth to democracy,” Mr Samaras said in a televised address.
A self-declared Golden Dawn supporter has confessed to the killing. The 45-year-old, pictured in Greek media with his arm around a Golden Dawn MP, is due to appear before a prosecutor tomorrow.
The party, Greece’s third most popular, condemned the killing and denied any part in it. It said its accusers were “wretched sycophants” out to win votes.
Golden Dawn, whose emblem resembles a swastika, rose from obscurity to win 18 seats in parliament in elections last year on an anti-immigrant and anti-corruption agenda. Its members have been seen giving Nazi-style salutes but the party insists it is not neo-Nazi.
Human rights groups have long accused the party of being linked to attacks on immigrants but this is the first time it has been investigated in relation to a specific incident.
Greece’s coalition partners have quarrelled over whether to ban it and several MPs have opposed the ban, saying it would boost its appeal and turn its members into martyrs. On Wednesday, citizen protection minister Nikos Dendias would only say the government would toughen laws against “criminal organisations and armed groups”, without giving details.
On Athens’ streets, talk was of Golden Dawn and austerity.
“The time has come for all of us to kick Golden Dawn out of parliament and tell Europe it needs to stop the austerity that is breeding these things,” said Lydia Montesanto, 62.
On Wednesday night, more than 5,000 people rallied on the spot where Fyssas was stabbed. Police fired teargas at protesters who threw stones and petrol bombs at a police station and set bins on fire.
Greece, the focus of the eurozone debt crisis, has been hit hard by years of recession brought on by austerity demanded by international lenders which have kept the economy afloat and in the euro bloc. Data this week showed the jobless rate dipping slightly in the second quarter, but still at a huge 27.1 per cent, with youth unemployment at 59 per cent.
The economic pain has sparked public anger, some directed at foreigners, prompting in part the rise of Golden Dawn. Yesterday, above a photo of a swastika in a red circle with a line through it, top-selling daily Ta Nea declared on its front page: “Enough is enough!”