The Norwegian gunman on trial for killing 77 people last year says he had planned to behead the country's former prime minister, Gro Harlem Brundtland, film the beheading and post the video online.

In his testimony in an Oslo court Thursday, the fourth day of his trial, 33-year-old Anders Behring Breivik also said he prepared for his assault by playing video games. He said he thought there was little chance of him surviving the attack.

Breivik, dressed in a black suit, white shirt and black tie, told the court he had been planning a larger attack for several years before pulling off the July 22 incident. He said he expected to be confronted by police after detonating a car bomb in Oslo, killing eight people.

He then traveled to nearby Utoya island where members of the youth wing of the Labor Party were holding a summer camp, and shot dead 69 people. Former prime minister Brundtland had visited the island but left before the gunman arrived. Breivik said he had wanted to kill all 600 people on the island.

Breivik, a far-right extremist, has admitted killing 77 people in attacks last July, but has pleaded not guilty to terrorism and murder charges, saying he acted in self-defense. He said his killing spree was designed to protect Norway from multiculturalism, and described the attacks as “spectacular.”

A key component of the trial is to decide whether Breivik was sane during the attacks. Norway does not have the death penalty, but if the court finds him guilty and sane, he will serve a maximum 21-year sentence, which could be extended if he were considered a continued danger.

Breivik has said an insanity ruling would be “worse than death.”