FILE - In this May 6, 2012 file photo, extreme right Golden Dawn party leader Nikos Mihaloliakos speaks during a news conference in front of a banner with the twisting Maeander, an ancient Greek decorative motif that the party has adopted as its symbol, in Athens. Greek police said Mihaloliakos was arrested on charges of forming a criminal organization. AP Photo/Petros Giannakourism, File FILE - In this Sunday, June. 10, 2012 file photo, Nikolaos Michaloliakos, leader of the extreme right-wing Golden Dawn party, waves to supporters during a pre-election rally at the northern port city of Thessaloniki Greece. Greek police said Mihaloliakos was arrested on Saturday Sept. 28, 2013, on charges of forming a criminal organization. Warrants for the arrest of the party's another five parliament deputies have been issued. The arrests come several days after the killing of a left-wing activist rapper by an alleged party member. AP Photo/Nicolas Giakoumidis, File 12, 2012 file photo, extreme right Golden Dawn party spokesman Ilias Kassidiaris, left, speaks with a retired special force military officer during a protest in Athens. Kassidiaris was arrested Saturday, Sept. Greek police also confirmed the arrest of the party leader Nikos Mihaloliakos on the same charges. AP Photo/Dimitri Messinis, File FILE - In this April 25, 2012 file photo, extreme right Golden Dawn party spokesman Ilias Kassidiaris poses next to the party flag and a statue of Alexander the Great, at the party headquarters in Athens. AP Photo/Petros Giannakouris, File ATHENS, Greece (AP) - Police arrested the leader of Greece's extreme-right Golden Dawn party and other top members on Saturday, in an escalation of a government crackdown after a fatal stabbing allegedly committed by a supporter. It is the first time since 1974 that sitting members of Parliament have been arrested. The arrests underline the Greek government's efforts to stifle the fiercely anti-immigrant party, which has been increasingly on the defensive since the killing. Police announced the arrests of 17 Golden Dawn members on charges of forming a criminal organization, including party head Nikos Michaloliakos, the group's spokesman and three other lawmakers. Of the six lawmakers targeted, only one remains at large. An operation by the counterterrorism unit was still ongoing early Saturday afternoon, with a total of about 35 arrest warrants for Golden Dawn members issued, two police officials said. They spoke on condition of anonymity because they were not permitted to speak publicly. "It is an unprecedentedly dynamic response to a neo-Nazi organization," government spokesman Simos Kedikoglou told The Associated Press, hinting that Saturday's arrests were the culmination of a long strategy to deal with Golden Dawn as a criminal, not a political force. "The prime minister and the government were determined to deal with Golden Dawn solely through the justice system...We have succeeded in stripping them of their political cover and deal with them as what they really are, a criminal organization," Kedikoglou said. The government ordered an investigation into Golden Dawn's activities after the death of rapper Pavlos Fyssas on Sept. 18 sparked outrage across Greece. The suspect arrested over his death admitted to police that he had stabbed the 34-year-old and identified himself as a supporter of Golden Dawn. Police investigated his cellphone records and those of over 300 persons connected to Golden Dawn. Investigations have extended to the police, which have been accused in the past of turning a blind eye to Golden Dawn violence and of mistreating immigrants. A police officer was also arrested on Saturday. The case is being handled by Greece's Supreme Court and anti-terrorist squad under organized crime laws. Despite the arrests, the party's lawmakers retain their parliamentary seats unless they are convicted of a crime. Golden Dawn holds 18 of Parliament's 300 seats, after winning nearly 7 percent of the vote in general elections last year. The party has vehemently denied any role in the killing, but the killing has appeared to dent its appeal among Greeks. As calls for a crackdown mounted, the party hinted its deputies might resign to provoke elections in 15 multi-party constituencies. "There will be no elections, certainly no general elections," Kedikoglou said. Asked about the likelihood of partial elections if Golden Dawn deputies were to resign, he said "there are ways to deal with that, as well." "Justice, stability, no elections," said prime minister Antonis Samaras, as he hurried from his office to the Athens airport on his way to a 6-day trip to the United States. Samaras was briefed on the arrests by two ministers during a break in his talks with representatives of Greece's creditors. Golden Dawn expressed outrage at the arrests in a text message to journalists. We call upon everyone to support our moral and just struggle against the corrupt system! Everyone come to our offices!," it said. A later text message called for supporters to head to police headquarters "with calm and order." A group of about 100 people, including several deputies, gathered, standing on the sidewalk across the street from the building. A formerly marginal organization with neo-Nazi roots, Golden Dawn entered Parliament for the first time in May 2012, capitalizing on Greece's deep financial crisis, rising crime and anti-immigrant sentiment. The party's members and supporters have frequently been suspected of carrying out violent attacks, mainly against immigrants. Despite its reputation for violence, the party had enjoyed growing popularity. Associated Press writer Elena Becatoros contributed to this report.