The Greek prime minister, Antonis Samaras, has appealed for calm, urging people to settle "differences democratically" after the murder of a leading leftwing musician allegedly at the hands of a member of the far right Golden Dawn party unleashed a wave of violent clashes overnight.  As thousands gathered in Athens to attend the funeral of the anti-fascist hip-hop artist Pavlos Fyssas, the conservative leader said his ruling coalition would not tolerate neo-Nazis destabilising the debt-stricken country.  "This is not a time for internal disputes or tension. We all know our country is at an extremely critical point," he told Greeks in a televised addressed referring to the bankrupt nation's worst financial crisis in modern times.  "Any political differences should be resolved through democratic dialogue … not through violence, and even more, not through blood."  With tensions running high between Greeks on the left and right following the stabbing of 34-year-old Fyssas, the beleaguered government has pledged to clamp down on Golden Dawn, arguably Europe's most extreme far-right group.  More than 300 attacks – starting with the murder of a Bangladeshi immigrant in May 2011 – have been attributed to the openly racist organisation whose meteoric ascent on the back of economic desperation has ensured it is now Greece's third-biggest party and fastest-growing political force. Recent opinion polls have shown it has the support of 15% of voters – more than double the figure it won in elections 14 months ago.  Highlighting the febrile mood, the deputy prime minister, Evangelos Venizelos, whose socialist Pasok party is the government's junior partner, insisted the ultra-nationalists "should be dealt with as a criminal organisation" because violence was their modus operandi.  Samaras's centre-right New Democracy party has been accused of soft-peddling on Golden Dawn for fear of further alienating traditional conservative voters who have migrated to the group since Greece plunged into fiscal chaos almost four years ago. In recent months ruling conservatives have ratcheted up their rhetoric in a bid to lure voters back.  "The Greek government has been inexcusably tolerant with the phenomenon that is Golden Dawn," a senior official told the Guardian.  "It is time that they be declared illegal. But the truth is, under the Greek constitution, it is very hard to ban Golden Dawn. The most we can do is apply the law when it is violated."  On Wednesday, the public order minister Nikos Dendias suggested the government would seek to ban the group by revising existing legislation.  Under government order Greek police continued to conduct raids on Golden Dawn offices around the country in an effort to find incriminating evidence of their violent behaviour.  On Thursday evening, in a letter to the ministry of justice, Dendias outlined 32 cases of attacks carried out by Golden Dawn with six involving members of its 18-strong parliamentary group. Police released photos of clubs, handguns and knuckle crackers found in the house of a Golden Dawn cadre that had been used in an attack in the central Greek city of Volos. In one case party members had threatened "to kidnap and cut off the ears of teachers" in schools hosting children of Pakistani and Indian immigrants.  But the extremists, who deny neo-Nazi links despite many privately applauding Adolf Hitler, have vehemently rejected allegations of criminality including the charge that they were behind Tuesday's killing.  Addressing parliament earlier on Thursday, the party's spokesman Ilias Kasidiaris said: "I want to remind all those in this house who pretend they are stupid and don't understand that from the first moment we have condemned this criminal act. In no way does our party have anything to do with it."  Earlier, Nikolaos Michaloliakos, Golden Dawn's leader, called on all of Greece's political parties to "assume their responsibilities and not create a climate of civil war by giving a political character to a tragic event".  But the murder has clearly shocked Greeks, already suffering the corrosive effects of six years of recession and punishing austerity.  Mourners shouted: "The people don't forget. Death to fascism," as they laid Fyssas to rest. The singer's father, a metal worker, publicly announced that he wanted his son's killer to be executed. "I want him not to be tried and imprisoned but executed. For me that is justice."  The alleged perpetrator, who is believed to have run the cafe at the offices of Golden Dawn in Keratsini, the working-class district where the killing occurred, has been given three days to prepare his defence before appearing before an investigating magistrate on Saturday.
Antonis Samaras says differences must not be settled with violence after Golden Dawn member is accused over killing