Norway held an emotional commemoration Sunday for the 77 victims of last month's twin attacks, with survivors, relatives, royals and pop stars all remembering the country's worst peacetime bloodshed. Some 6,700 people gathered in the Spektrum concert hall in Oslo in a display of unity, almost exactly a month after Anders Behring Breivik bombed the government quarter before mowing down participants at a youth camp. "Nearly all words have been used by now," King Harald V said, choking back tears as he opened the ceremony. "These last weeks have been difficult for us but it's doing all of us good to be gathered here today," the monarch said. The ceremony was due to include a speech by Prime Minister Jens Stoltenberg, who has a emerged as a hugely popular figure since the massacre, and a performance by the A-Ha pop group, which was reformed for the occasion. Between passages of music, Norwegian actors will read aloud the names of the 77 victims, mostly young people, who perished in the attacks perpetrated by Behring Breivik on July 22. The ceremony is directed by Haddy N'jie, born of a Gambian father and Norwegian mother, thereby representing the mixed-race society explicitly rejected by the killer. The 32-year-old rightwing extremist set out his hatred of Islam and Norway's tolerance of multiculturalism in a 1,500 page document posted on the Internet before detonating a bomb in central Oslo and going on the rampage on the island of Utoeya, where the ruling labour party was holding a summer youth camp. The ceremony's audience also included several foreign dignitaries, notably the presidents of Iceland and Finland, Olafur Ragnar Grimsson and Tarja Halonen, all the prime ministers of the Nordic countries, Crown Princess Victoria of Sweden and Prince Fredrik of Denmark. On Saturday survivors from the youth camp made a difficult, first return to Utoeya, where 69 of their friends were gunned down in cold blood in the hopes of finding some closure to their ordeal. The day before, relatives of the dead were given their opportunity to visit the island, 40 kilometers (25 miles) northwest of Oslo, where their loved ones spent their last moments alive. As around 500 relatives made their pilgrimage on Friday, Behring Breivik made a new appearance in court, when a judge ordered him to be kept in solitary confinement for another month in the maximum security jail near Oslo where he is being held. The gunman, who has confessed to the killings but insisted they were "cruel" but "necessary", protested at the judge's decision as "sadistic torture".