Norway's attorney general on Friday appealed a court ruling that partially upheld the claims of mass killer Anders Behring Breivik that he is subjected to prison conditions that violate his human rights.
The conditions Breivik was serving his sentence under did not constitute "inhumane or degrading treatment," the state's attorneys said.
Further, the Oslo District Court had not taken into account that Breivik's conditions were in accordance with assessments of the potential threat he still poses to society and visitors, the 16-page appeal read.
The Norwegian right-wing extremist, who killed 77 people in 2011, had sued the state and prison authorities over restrictions he faces while serving his 21-year prison sentence for the attacks, considered the worst acts of violence in Norway since World War II.
The Oslo court on April 20 ruled in favour of Breivik over his complaints about time spent in isolation and his limited ability to complain.
The court said the terms "represent an infringement of article three of the human rights convention," referring to law against inhumane treatment.
A hearing held in March at Skien prison, south of Oslo, was the first time Breivik was seen in public since his 2012 trial.
Friday was the final date for appeals to be lodged. The justice minister had at the end of April said an appeal was due.
Breivik said the aim of his attacks was to punish the Labour Party, then in office, over its failure to stem the flow of Muslim immigrants to the country.