Breivik detonated a car bomb in Oslo killing eight people before traveling to Utøya island disguised as a police officer, where he hunted down and shot young campers for over an hour before surrendering. The twin attacks, the deadliest on Norwegian soil since World War II, were driven by Breivik's virulent anti-immigrant, anti-Muslim ideology laid out in a sprawling manifesto.
On the afternoon of July 22, 2011, a car bomb ripped through Oslo's government quarter, killing eight people and shattering windows across the district—an attack initially assumed to be Islamist terrorism. It was, instead, a diversion. Its perpetrator, Anders Behring Breivik, a Norwegian far-right extremist, then drove to a ferry landing and crossed to Utøya island, dressed in a police uniform and carrying legally purchased weapons.
On Utøya, roughly 600 teenagers and young adults were attending the Workers' Youth League's annual summer camp. Breivik began shooting methodically, chasing victims across the small island, some of whom swam into the cold water in desperate escape, for more than an hour before police—delayed by logistical failures—arrived to arrest him. He killed 69 people at the camp, most of them teenagers, adding to the eight killed in Oslo.
Breivik's 1,500-page manifesto detailed a paranoid ideology obsessed with 'Islamization' and multiculturalism, chillingly methodical in its planning. His trial and subsequent 21-year sentence—the maximum under Norwegian law, extendable indefinitely—sparked a national reckoning over how a peaceful, famously open society had produced, and failed to detect, such violence, and it hardened debates across Europe about far-right extremism and immigration.