Anders Behring Breivik, the jailed mass murderer who killed 77 in Norway's worst peacetime atrocity, told a court his attacks were "necessary" as he asked for early release on Tuesday, but a prosecutor said he remained dangerous and should not be freed.

Norwegian far-right extremist Anders Behring Breivik, who killed 77 people in a bombing and shooting rampage in 2011, has made another application for parole after spending more than a decade behind bars.

It will be Breivik's second attempt at parole. He is serving a 21-year sentence, the maximum penalty at the time of his crimes, which can be extended for as long as he is deemed a threat to society. Breivik became eligible to seek parole after serving the first ten years of his term.

Breivik appeared in court on Tuesday seeking release after over 13 years in prison. It is Breivik's second attempt at parole. Breivik, 45, wearing a dark suit, white shirt and brown tie sat impassively as she spoke.

A new court hearing began in Norway on Tuesday regarding the prison term of convicted mass murderer Anders Behring Breivik, 13 years after the far-right terrorist attacks in Oslo and on the island of Utøya which left 77 people dead.