A man who lost a son squeezed his eyes shut. A man to his left put a comforting hand to his shoulder, while a woman to his right clutched onto him, resting her forehead against his arm.
Tore Sinding Bekkedal, 24, a survivor of the massacre, left the courtroom during Breivik's testimony. "I could not care less about what he says or the way he says it," Bekkedal said. "I do not care about him as a person."
Breivik has confessed to the July 22 bombing-and-shooting rampage that killed 77 people - 69 on Utoya and eight in Oslo. But he rejects criminal guilt, saying the victims had betrayed Norway by embracing "Islamic colonization."
Looking tense but focused, Breivik spoke calmly about his actions, beginning with a ferry ride to the island, where the governing Labor Party holds its summer youth camp. He was disguised as a policeman, carrying a rifle and a handgun.
Breivik's first victims were Monica Boesei, a camp organizer, and Trond Berntsen, an off-duty police officer and camp security guard.
"My whole body tried to revolt when I took the weapon in my hand. There were 100 voices in my head saying 'Don't do it, don't do it,' " Breivik said.
Nonetheless, he pointed his gun at Berntsen's head and pulled the trigger. He shot Boesei as she tried to run away. Then as they lay on the ground, he shot them both twice in the head.
Breivik said the first shots pushed him into a "fight-and-flight" mode that made it easier to continue killing.
He couldn't remember large chunks of the 90 minutes he spent on the island before surrendering to police commandos. But he recalled some shootings in great detail, including inside a cafe where he mowed down young victims as they pleaded for their lives.
Some teenagers were frozen in panic, unable to move even when Breivik ran out of ammunition. He changed clips. They didn't move. He shot them in the head.
"They cannot run. They stand totally still. This is something they never show on TV," Breivik said.
Earlier, Breivik said he took to the Internet to glean information, studying attacks by al-Qaeda militants, Oklahoma City bomber Timothy McVeigh, and the 1993 bombing of the World Trade Center.
The main goal of the trial is to determine whether Breivik was sane or insane. Two medical evaluations have come to opposite conclusions.