Anders Breivik made a far-right salute as he arrived at a courtroom to face trial over the the murders of 77 people in Norway last year, and has interrupted proceedings to say that he does not recognise the Norwegian court.
He told judge Wenche Elisabeth Arntzen: "I do not recognise the Norwegian courts. You have received your mandate from political parties which support multiculturalism. I do not acknowledge the authority of the court."
Breivik stood up again to confirm his date of birth and that he was currently in prison. The judge said: "And you are unemployed?"
Breivik sipped water as horrific details of his mass killings were read out in court
Breivik replied: "That is not correct. I am a writer and I work from prison."
The 33-year-old showed no emotion as the judge read out the names and details of the people he killed in the shooting spree, the youngest of whom was just 14.
Wearing a dark suit and metallic-coloured tie, he looked down and touched his chin as the gruesome details of their deaths were read out.
He told the judge: "I do not recognise the Norwegian courts"
Some of the details of the murders and injuries were so horrific the Norwegian media bleeped them out.
Overall 102 names, dates of births and details of those Breivik killed and injures were read in court over 30 minutes.
After hearing the charges, Breivik said it was "self defence," telling the judge: "I acknowledge the acts but I do not plead guilty, I claim that I was doing it in self defence."
The killer looked composed as he was handcuffed and led out of the court for a 20 minute break.
The prosecutor Svein Holden's opening statement focused on how Breivik was radicalised.
Holden said the killer claimed to be part of a secret organisation dedicated to removing Islam from Europe and modelled on the medieval Christian military order the Knights Templar. But the prosecutor said in their opinion "no such network exists."
Police have not been able to substantiate his claims of being in a group and believe he acted alone.
On Monday the prosecution detailed how Breivik sold fake diplomas on the internet and played the computer game World of Warcraft "extensively" in 2006.
During the trial, the court will be shown videos of his attacks so gruesome they will not be broadcast on TV like the rest of the trial.
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One of the survivors of the massacre Jorid Nordmelan, who will hear Breivik testify, said the trial was unprecedented.
"It's a historical date for Norwegians," she told the BBC. "We never had a trial like this, so we don't know what's going to happen.
Armed police walk in the street outside the Oslo district courtroom
"Prosecutors told me they were going to make the opening statements awful, so that people can just feel what he did right there."
He is due to give evidence for five days, explaining why he set off a bomb in Oslo, killing eight, before gunning down 69 people, mostly teenagers, at a Labour Party youth camp on Utoya island, outside the Norwegian capital.
Since Breivik has confessed to the July 22 attacks - claiming they were necessary to protect Norway from being taken over by Muslims - the key issue that remains unresolved is his mental health.
Breivik attempted to justify his views in a 1,500-page manifesto published on the internet before the atrocities.
The police van with terror charged Anders Behring Breivik leaves the Ila prison in Baerum, Norway
The carnage caused by Anders Breivik began with a bomb in Oslo.
Eight people were killed when his device exploded at the high-rise building in Oslo at 3.26pm local time on 22 July last year.
It left a dust-clogged square covered in twisted metal and shattered glass.
Police described it as an "Oklahoma city-type" bombing, targeting a government building, perpetrated by a home-grown assailant and using the same mix of fertiliser and fuel that blew up a building in the US in 1995.
But as police battled to deal with the effects of the bomb, a much more deadly attack was about to begin 20 miles north-west of the capital.
Prosecutors showed images of Breivik taken from his manifesto. A badge on the uniform read "Marxist Hunter"
Breivik, dressed as a policeman, drove to a lake outside the capital and took a ferry to the island of Utoya, where hundreds of young people were attending a summer camp organised by the youth wing of the Labour Party.
At around 4.50pm he opened fire, claiming another 69 lives. It is claimed that he beckoned to his young victims before shooting them one by one.
Survivors of the shooting spree described hiding and fleeing into the water to escape.
Police arrived on the island an hour and a half after the gunman first opened fire, because they did not have quick access to a helicopter and could not find a boat to reach the scene just several hundred yards away.
When the armed officers did locate a boat they overloaded it, causing it to breakdown.
Breivik surrendered when officers finally reached him on Utoya at 6.35pm.
Oslo police director Oeystein Maeland said later: "I regret we weren't able to arrest the suspect earlier than we did."
He went on: "Could police have been faster? The answer is yes.
"If the boat hadn't been over capacity, police would have been on Utoya faster."
Mr Maeland added: "If it would have led to another and better result is nothing we know for sure, but we can't rule it out. And it's tough, like I've said before, to think that lives thereby would have been saved."
Chilling accounts soon emerged of what happened at the camp.
A 15-year-old, Elise, said she heard gunshots but then saw a police officer and thought she was safe. Then the man started shooting people in front of her.
"I saw many dead people," she said.
"He first shot people on the island. Afterwards he started shooting people in the water."
Dana Berzingi, 21, said several victims "had pretended they were dead to survive".
But after shooting them with one gun, he blasted them in the head with a shotgun, he added.