Oslo, Norway (CNN) — Norway will pay tribute Friday to those killed and injured in two terror attacks a week ago, with a memorial service in Oslo organized by the youth movement of the Labour Party.

Political leaders and the relatives of the victims are expected to attend the service, at which Prime Minister Jens Stoltenberg, the Labour leader, will be among the speakers.

The party’s youth movement was targeted in a mass shooting that claimed at least 68 lives on Utoya island, where it was holding a summer camp. Eight people were also killed in a bombing that hit government offices in Oslo.

Meanwhile, Anders Behring Breivik, the suspect in last week’s terrorist attacks, will be interrogated for a second time Friday, Oslo police chief Johan Fredriksen said.

Investigators are ready to question Breivik again as they have gained new information since he was first interviewed a day after the attacks, police attorney Pal-Frederick Hjort Kraby said.

He is likely to face more interrogations in the coming weeks.

Breivik is being kept in solitary confinement at Ila Prison, near Oslo, which held Nazi prisoners during World War II.

“We are giving him pillow, sheet and shelter for a few weeks,” the prison governor said.

He only has contact with his lawyer and prison staff who bring him food, Kraby said.

Breivik has admitted carrying out the bombing in Oslo, in which eight people died, and the shootings on Utoya, his lawyer and a judge have said. He has pleaded not guilty.

The first funeral for a victim of the attacks will take place Friday at 1 p.m. local time, as Bano Rashid, 18, is laid to rest in a Christian and Muslim ceremony at a church.

She was a Kurd who came to Norway with her family in 1996 after fleeing from Iraq, state broadcaster NRK reports.

Flags on government buildings are to fly at half mast Friday as a mark of respect, a week on from the attacks.

Meanwhile, the search for more victims of the shooting rampage on Utoya island has ended, the police chief said Thursday. However, later in the day, the police website said the search in the water around the island was ongoing.

More than 50 investigators remained on the island and will likely remain there for several more weeks, officials said.

Sixty-eight people are confirmed dead in the attack on the island, where a summer camp for the Labour Party’s youth movement was taking place. As of Thursday, authorities had released the identities of 41 of the dead.

A key question for investigators is whether Breivik acted alone.

“At this moment in time we don’t think there are more people involved in this action, and we don’t know whether there are more bombs,” said Janne Kristiansen, director of the Norwegian intelligence police.

But she downplayed the possibility of further carnage.

“We think, more than likely, he has been on his own and nothing is going to happen here,” she said. “So people should go on living their lives.”

She said Breivik acted lawfully during his preparations, registering his weapons and using his farm as a front to collect the fertilizer that powered the bomb. His meticulousness extended to his communications with others, even in his Internet messages, which were “very moderate,” she said.

“He has been what we call a lone wolf,” she added. “With a lone wolf, they always operate alone, having no accomplices anywhere, and this is, obviously, what he has done.”

But, she added, “We believe that he might have had contacts in the rest of the world and we’re investigating this.”

His primary goal: “The focus from the world press, which he now has,” Kristiansen said. “He’s totally evil, and he’s using us, and he’s using you — especially the media — to bring forward his voice.”

Police predicted that most of the court hearings attended by Breivik will be closed to the public.

CNN’s Laura Smith-Spark and Nic Robertson contributed to this report.