(CNN) -- The families of the victims of a mass shooting rampage on a Norwegian island are visiting the scene Friday, a month after two attacks plunged the Scandinavian nation into mourning.

Sixty-nine people died July 22 on Utoya island, where hundreds of mostly young people were gathered for a summer camp held by the youth wing of the governing Labour Party. Eight others died in the bombing of Oslo government buildings hours earlier.

TV footage showed the first group of relatives of victims of the shooting walking in line as they arrived on Utoya island in the rain.

"It is a very important and emotional day for these families," Health Minister Anne-Grete Strom-Erichsen said, according to Norway's official NTB news agency.

A policeman will show each family where their loved one was found after the attack, NTB reported. The families will also be accompanied by Red Cross representatives.

Many of the 69 families affected have said they plan to visit the island over the weekend, Norwegian reports say.

Meanwhile, a judge ruled that Anders Breivik, the man accused of carrying out both attacks, should be held in solitary confinement for another four weeks because there was a real danger he would otherwise tamper with evidence.

This was especially important because the police have still not established whether Breivik had accomplices, Judge Hugo Abelseth said.

He told the court in Oslo that the police request for Breivik to remain in isolation outweighed the suspect's concerns.

Breivik, 32, had told the court that being held in isolation is "boring, monotonous and a sadistic method of torture," the judge said.

Breivik appeared in court to hear the arguments but the session was not open to the public or media. He will remain in solitary confinement until September 19, Abelseth said.

At an initial court appearance for Breivik last month, the police were granted eight weeks' custody, four of them in isolation. Suspects are not normally held in isolation for longer than two weeks in Norway, according to local media reports.

Speaking after Breivik's court appearance, Paal-Fredrik Hjort Kraby of Oslo Police District told reporters that the suspect was being kept cuffed by his hands and feet, and also chained at the waist.

He said several survivors of the Utoya massacres had wanted to be present at the court hearing, but that the police had decided it was too risky in case they unwittingly revealed details of the case that would enable Breivik to alter his explanations.

The police instead allowed four of the 113 lawyers representing the survivors, victims and their families to be present at the hearing, Kraby said. Survivors may be allowed in court when the investigation is no longer at such a sensitive point, he said.

Kraby also responded to questions about the revelation by police Thursday that Breivik had made two calls to the police while on Utoya island on July 22.

Officers had not called Breivik back because they say no number came up on their display. The most likely explanation for this is that the phone was not equipped with a SIM card or subscriber identity module, Kraby said, which would have transmitted the phone's number.

Police chief Sissel Hammer on Thursday confirmed that Breivik had made two calls, one to Nordre Buskerud district and another to Sondre Buskerud Police district.

According to a police transcript of the calls, Breivik said: "Hello, my name is commander Anders Behring Breivik of the Norwegian anti-communist resistance movement." After the police operator responded, he said: "I am at Utoya. I wish to surrender."

Kraby said Breivik had been questioned for a total of 60 hours. He has not been questioned this week but questioning will resume next week.

It is too early to tell what the final charges against Breivik will be, Kraby added, as the police are still systematically collecting and evaluating evidence and information.

Breivik's lawyer said his client was concerned about appearing smart and respectably dressed for Friday's court appearance, state broadcaster NRK reported.

During the past four weeks in solitary confinement, Breivik has been given more clothes, a clock and books, as well as a computer that is not connected to the internet, NRK said. He has not had been allowed any visitors, letters or media access.

Breivik was taken back to Utoya -- which remains a crime scene -- on Saturday as part of a police investigation into the rampage.

Police said they spent nearly eight hours questioning Breivik and walking with him around the island during a reconstruction of the attack. They said he "was not emotionally unmoved," but did not express remorse during his return to the scene.

Breivik has been held in solitary confinement since he was taken into custody on the island on July 22.

He has admitted carrying out the attacks, his lawyer and a judge have said, but has pleaded not guilty in court.

The ages of the 77 people killed in the twin attacks ranged from 14 to 61, with an average age of 21, the government said.

CNN's Cynthia Wamwayi and journalist Olav Mellingsaeter contributed to this report.