Thousands of people in Greece have protested against far - right extremism in the country following the murder of a leftist musician by a suspected neo - Nazi.On Thursday, approximately 4,000 people, mostly trade union members, staged a rally in Keratsini in western Athens, carrying banners reading "Stop fascism," AFP reported. The protesters shouted slogans including, "Out with fascists" and "Workers do not fear threats." The protest rally came after Pavlos Fyssas, a 34-year-old hip-hop singer and an anti-fascist activist, died in a state hospital on Wednesday after being stabbed twice outside a cafe in Keratsini. A 45-year-old man, who admitted to the killing and an alleged member of the group, was arrested at the scene. The death drew condemnation from across Greece's political spectrum and from abroad. Government spokesman Simos Kedikoglou blamed the killing on the Golden Dawn party, which has denied any connection to the murder and condemned the group's "raw violence" and called on other parties to "raise a barrier to the vicious circle of tension and violence." Prime Minister Antonis Samaras also lashed out at the party in a televised address to the nation on Thursday, saying, “This government is determined not to allow the heirs of the Nazis to poison our social life, to commit crimes, to terrorize and to undermine the foundations of the country that gave birth to democracy," Secretary General of the Council of Europe Thorbjoern Jagland also expressed concern over the incident, warning that an “extremely dangerous development” is emerging in Greece and in other parts of Europe. “Sections of society are becoming more radicalized, and there is a real risk that hate speech turns into violence and coldblooded murder,” Jagland noted, saying that he plans to visit Greece in October for discussions with Greek authorities over the violence in the country. On Wednesday, violent clashes erupted between Greek police forces and anti-fascist protesters who staged demonstrations in different cites against the killing of the leftist musician.