OSLO - The Norwegian anti-Islamic militant who massacred 77 people last summer arrived at an Oslo courthouse under armed guard on Monday, clenching his fist in a far-right salute and saying he did not recognize the authority of the judges.Anders Behring Breivik, 33, has admitted setting off a car bomb that killed eight people at government headquarters in Oslo last July, then killing 69 in a shooting spree at a summer youth camp organized by the ruling Labor Party.Breivik calls court a "circus""Your arrest will mark the initiation of the propaganda phase," he wrote in a manual for future attackers, part of a 1,500-page manifesto he posted online."Your trial offers you a stage to the world."In a recent letter seen by Norwegian newspaper VG, Breivik added: "The court case looks like it will be a circus ... it is an absolutely unique opportunity to explain the idea of (the manifesto) to the world."Last July 22, he set off the bomb before heading to the youth camp on Utoeya island in a lake 40 km outside Oslo, gunning down his victims while police took an hour to get to the massacre site in the chaos following the blast.Breivik has said he intended his attacks as punishment of "traitors" whose pro-immigration policies were adulterating Norwegian blood.An initial psychiatric test concluded that Breivik was criminally insane while a second one, completed in the past week, found no evidence of psychosis. Resolving this conflict could be the five-judge panel's major decision.If found sane, Breivik faces a maximum 21-year sentence but could be held indefinitely if he is considered a continuing danger. If declared insane, he would be held in a psychiatric institution indefinitely with periodic reviews.The courthouse, accessible through airport-style security, is already barricaded by TV trucks as 200 media organizations have descended on Oslo, home of the Nobel Peace Prize.The courtroom, the country's biggest, can seat just over a tenth of the journalists, victims and relatives who may wish to attend, so closed-circuit viewing rooms have been set up nearby and in 17 other courthouses around Norway.Breivik's proposed witnesses include Mullah Krekar, the Kurdish founder of Islamist group Ansar al-Islam, who was recently jailed in Norway for making death threats, and "Fjordman", a right-wing blogger and influence on Breivik.Norway's legal system gives defendants wide leeway to defend themselves as they wish, but judges can trim the witness list.The trial will also examine Breivik's initial claim that he was part of an organization of "Knights Templar" with similar views. Police said evidence now points to solitary attacks by Breivik after years of radicalization.Lone wolf attackers have become an increasing security risk worldwide, with US President Barack Obama last year saying they now pose a greater danger than large, coordinated actions.Breivik entered the court in handcuffs, which were taken off just before he was seated. He smirked several times as the cuffs were removed, put his right fist on his heart then extended his hand in salute."I do not recognize the Norwegian courts. You have received your mandate from political parties which support multiculturalism," Breivik told the court. "I do not acknowledge the authority of the court."The "lone wolf" killer intends to deny criminal guilt, saying he was defending Norway against multiculturalism and Islam. The trial is scheduled to last 10 weeks, during which the court must rule on both his guilt, and his sanity.More than 200 people took seats in the specially-built Oslo courtroom while about 700 attack survivors and family members of victims watched on closed-circuit video around the country."Today the trial starts, and it will be a tough time for many," survivor Vegard Groeslie Wennesland, 28, said outside the courtroom. "Last time I saw him in person he we was shooting my friends."Some Norwegians fear Breivik will succeed in making the trial, with about 800 journalists on hand, a platform for his anti-immigrant ideas. His defence team has called 29 witnesses, ranging from Islamists to right-wing bloggers, to shed light on his world view.Breivik is scheduled to testify for about a week, starting on Tuesday.