Oslo:
Addressing a courtroom frozen in horror, Breivik said he shot most of his victims several times, using the first shot to take them down, then following up with a shot to the head.
His trial, now into its fifth day and due to last 10 weeks, has deeply traumatised Norway, one of the most tolerant and stable countries in Europe.
Speaking intensely, the steely-eyed Norwegian described how his body tensed up as he fired his first shots at the ruling Labour Party's youth camp on Utoeya island.
"I took the gun out and thought it was now or never, and it seemed like a year," he said.
He described how he then went on his rampage, gunning down 69 people, most of them teenagers.
"When I make a follow up shot, his (victim's) cranium bursts and there are brains flowing out. I remember that very well," Breivik said in an unemotional, matter-of-fact tone.
His victims, he said, appeared paralysed before he shot them. "I walk towards a group of 10 who have stopped. They have stopped running and just lie down. I go to them and shoot them all to the head. They were paralysed most likely."
Victims' families have found it difficult to see Breivik using the trial as a pulpit to justify his views and violence.
Breivik, 33, admits the killings but has pleaded not guilty. He says he was defending his country against Muslim immigrants by setting off a car bomb that killed eight people at government headquarters in Oslo before travelling to the island to carry out the massacre.
"It was extremely hard to shoot that first shot, it is contrary to human nature. But after that... it became easier," he said. "To take a human life is the most extreme you can do, but you weigh that against superior motives."
He began the shooting after arriving by boat dressed as a police officer. Many victims were shot as they tried to swim to the mainland almost a kilometre away or huddled behind rocks on the shore.
"Calmly I raised my rifle... and shot from a distance toward these people. I know that I hit at least four of them."
"I shouted on two occasions, you are going to die today, Marxists... and people panicked completely," Breivik told the somber and completely silent courtroom. "The object was to kill everyone on the island by scaring them into the water."
He insists he is mentally stable and demanded that his attacks, the most violent in Norway since World War Two, be judged as political militancy and not the work of a madman.
Breivik said the first place he met a large group of campers was in the island's cafe building, where police said he killed 13. He then left the cafe for the so-called Lovers' Path, where 15 people died, then the pump house, where 14 died, and other island landmarks that most Norwegians now know by heart.
In one room alone, he said: "I shoot perhaps four or five persons. I think I shoot them once in the head first, until I have shot them all, and then I fire follow-up shots afterwards."
He reloaded. One person tried to attack him but was shot.
"Many people scream and beg for their lives. I don't really remember what they were saying."
TRAININGPolice have said there were 564 people on the wooded island at the time and Breivik told the court he had hoped to kill all of them, including former Norwegian Prime Minister Gro Harlem Brundtland who was there that day.
On Thursday, he told he had planned to chop her head off and upload film onto the Internet, but Brundtland had left Utoeya several hours before he arrived.
On Friday, Breivik said he began training consciously five years before the attacks in order to suppress his feelings, after he decided to use violence to alert Europeans to what he considered the loss of their culture.
His training included playing computer games up to 16 hours a day and practicing daily meditation to "hammer away" at emotions and embrace his own death, he said.
"One might say that I was quite normal until 2006 when I started training, when I commenced de-emotionalising," he told the court. "And many people will describe me as a nice person or a sympathetic, caring person to friends and anyone."
"I've had a dehumanisation strategy towards those I considered valid targets so I could come to the point of killing them. ... It is easy to press a button and detonate a bomb. It is very, very difficult to carry out something as barbaric as a firearms operation."
When asked about his feelings, Breivik said he recognised the suffering he had caused but that he remained detached from it. His mental training regimen was similar to that which Norwegian soldiers undergo to serve in Afghanistan, he said.
Before the trial, one court-appointed team of psychiatrists concluded Breivik was psychotic, while a second found him mentally capable. He has said he should either be executed or acquitted, calling the prospect of a prison sentence "pathetic" and an insanity ruling "worse than death".
Defence attorney Geir Lippestad told Reuters that Breivik's only goal at the trial is to prove himself sane.
"He thinks he has explained his views satisfactorily, the way he wishes, and he thinks that people understand what he is saying, at least the group he talks to," Lippestad said.
Copyright @Thomson Reuters 2012