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.

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.

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.