(CNN) -- The suspect in Norway's July 22 terror attacks has told police he had plans to attack other targets, Norwegian police said Saturday.
Anders Behring Breivik was interrogated Friday for the second time since his arrest, which followed the bombing of Oslo government buildings in which eight people died and a shooting rampage on an island which killed 69.
Police declined to say what the other targets were.
They also offered no comment when asked about reports that Norway's royal palace and the Labour Party headquarters were targets.
The new details emerged during an interrogation of the suspect that lasted almost 10 hours, police attorney Pal-Frederick Hjort Kraby told reporters.
Breivik was "more than willing to co-operate" with officers questioning him, and was calm and willing to explain himself, Kraby said.
The first part of the interview focused on going back over what he had told police the first time he was questioned, a week ago, Kraby said.
Then police questioned him about his movements in the government area of central Oslo before, during and after the bomb blast there, the attorney said.
His answers will be checked against footage from video cameras in the area, Kraby added, as police seek to make sure he was not working with anyone else.
Individuals who have been in contact with the suspect will also be of interest to police, the lawyer said. His mother has been formally interviewed.
Breivik is expected to be interviewed many more times in the weeks ahead, with investigators likely to ask more questions rather than just letting him talk, Kraby said.
Breivik is being kept in solitary confinement at Ila Prison, near Oslo, which held prisoners of the Nazis during World War II. His sole contacts are with his lawyer and prison staffers who take food to him.
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 also pleaded not guilty in court.
The attack on Utoya targeted members of the Labour Party's youth movement as they attended a summer camp.
On Friday, Norwegian authorities completed the identification of the dead, releasing the names of all 77. Their ages ranged from 14 to 61, with an average age of 21.
Earlier Friday, Prime Minister Jens Stoltenberg, other political leaders and relatives of the victims attended a memorial service organized by the Labour Party youth movement to commemorate those killed and wounded.