Norwegian police have revised their casualty figures for a mass shooting and bomb attack last Friday, lowering the number of people killed to 76.

Police say a gunman killed 68 people on Utoeya Island, where hundreds of young people had gathered for a summer camp organized by the ruling Labor Party. Officials say the previous figure was inflated due to confusion at the site. They also raised the number of people killed in a car bombing in Oslo's government district to eight.

The 32-year-old suspect, Anders Behring Breivik, made his first court appearance at a closed hearing in Oslo. He has confessed to both attacks, while denying he committed any crime.

After the hearing, the judge reported Breivik said he wants to “save Europe” from a Muslim takeover and belongs to a network with two other cells.

The court ordered Breivik to be detained for eight weeks, including solitary confinement for the first four weeks. The judge said the measures are necessary to prevent the suspect from interfering with the police investigation.

According to prosecutors, Breivik says he expects to spend the rest of his life in prison.

Meanwhile, Prime Minister Jens Stoltenberg led the nation in a minute of silence for the victims of the attacks, the deadliest in Norway since World War Two. He announced the start of the silent tribute on the steps of Oslo University, flanked by Norway's king and queen.