The trial of Anders Behring Breivik was interrupted on Friday after a man threw a shoe at the confessed mass killer, in the first such outburst since the proceedings began last month, the Norwegian newspaper VG reported.

The unidentified person screamed "Go to hell! You killed my brother" before security staff escorted him from the courtroom in the Norwegian capital, Oslo.

The shoe hit Breivik's defense lawyer.

Breivik, 33, has confessed to murdering 69 people at a youth summer camp on Utoeya Island and eight in a bomb attack in Oslo on July 22, 2011, but pleaded innocent to terror charges, saying he was defending Norway from multiculturalism and immigration.

Friday's incident was followed by cheers from several members of the public in the courtroom.

If he is found to have been sane, Breivik will face Norway's maximum 21-year jail sentence.