A couple stands in front of a wall decorated with flowers in memory of the victims of last Friday's attacks, in Oslo July 29, 2011. Norwegians united in mourning on Friday as the first funerals were held a week after anti-Islam zealot Anders Behring Breivik massacred at least 76 people in attacks that traumatized the nation. [Photo/Agencies]

"He is calm, he behaves calmly," his lawyer Geir Lippestad told NRK public television. He said Breivik showed no remorse, saying the killings were "a necessary act ... a war against the rule by Muslims".

The Norwegian Police Security Service said Breivik probably acted alone, doubting his statements that he was a member of a wider group of "Knights Templar".

"The terrorist acts bring no increase in the threat from known extreme right or left-wing groups in Norway," it said.

"It is most likely that the perpetrator planned and carried out the actions with no support from others," it said, calling the bombing and shooting "unique both in a national and international context".

Summer camps

At the Labour party memorial, Eskil Pedersen, head of the Labour youth movement, said the group would return to Utoeya. "We have taken our country back ... we will take Utoeya back," he said.

An opinion poll indicated support for Labour had leapt about 10 percentage points in the days after the attacks. Stoltenberg has won praise for his calm handling of the crisis.

The poll, for newspaper Sunnmoersposten, found Labour's support jumped to 38.7 percent immediately after the attacks from 28.1 percent just before, in a two-part poll each covering about 500 people in the days around July 22.

At the same time, support for the populist right-wing Progress Party, of which Breivik was once a member, fell along with backing for the opposition Conservative party.

The Progress Party became the second biggest in parliament after a 2009 election on an anti-tax and anti-immigration platform, but says Breivik was not an active member.

A court has appointed two psychiatrists to try to discover why Breivik staged his attacks, with a mandate to report back by Nov 1. His lawyer has said he is probably insane.

Norway plans to set up an independent "July 22 Commission" to examine the attacks, including investigating whether police reacted too slowly to the shootings at Utoeya island, when Breivik was able to kill for more than an hour.

Police have said officers drove to Utoeya from Oslo because they had no helicopter available.