July 25, 2011 — -- Swimming 100 meters off the shore of Utoya island in Norway, Kristoffer Nyborg was relieved when he saw a policeman approaching a group of terrified teens on the shore. Gunfire had erupted on the island just moments before, and Nyborg had already seen children murdered. He thought that at least the group on the shore would be safe.
"But then he took out his weapon and executed them," Nyborg said.
Nyborg, 24, had been working at the Norwegian Labour party youth camp Friday when a gunman wearing a police uniform, identified by authorities as 32-year-old Anders Breivik, opened fire on the defenseless youths. Before it was over, at least 68 people would be killed.
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In an interview with ABC News, Nyborg said that the shooting started just after there had been a group talk about a deadly bombing in Oslo just a few hours before -- also the work of Breivik, according to police.
Nyborg saw kids running and shouting about a shooter so he ran as well. When he came across a group of 10 youths, they tried to make their way to the shore. Before they made it, Nyborg said he saw three girls gunned down in the distance.
"It wasn't like the movies where you see blood," he said. "There was no blood. They just fell, lifeless."
When his group made it to the shore they joined approximately another 20 children, aged 13-19. In a snap decision, he told them they had to swim to save their lives. Nyborg led the youths into the water, but a handful were too panicked to get in.
Then he saw the man in the police uniform approach the kids left on the beach. "I thought they were all saved," he said. After the man opened fire into the group, he turned his weapon on Nyborg and the other swimmers.
Nyborg said he thought he was going to die and he saw at least one girl swimming with him sink below the surface after bullets ripped through the water all around them.
Despite his efforts, Nyborg said only he and three others made it all the way to the closest shore. The rest grew too tired and turned back to the island -- back to the massacre. He said he doesn't know if any of them made it out alive.
Breivik, who posted an extreme right-wing online manifesto, appeared in his first court hearing today and confessed he was behind the bombing and the shooting. He said he was not guilty, however, and that he was trying to change Norwegian society for the better by attacking the Labour party for "treason."
READ: Norway Shooting Suspect: Attacks Were 'Price of Their Treason'