Norwegian mass murderer Anders Breivik performed a Nazi salute to a court that will decide whether his human rights have been violated in prison.
Judges were reviewing claims the right-wing extremist's solitary confinement is inhumane.
In 2011, the 37-year-old shot dead 69 people at a summer camp for young centre-left political activists, after killing another eight people in a car bomb in Oslo earlier that day.
Dressed in a dark suit, Breivik stared at reporters while making the salute, saying nothing.
Judge Oystein Hermansen asked him not to do it again, saying it insulted the dignity of the court.
A district court ruled in his favour last year, saying his solitary confinement, frequent strip searches and treatment in prison violated his human rights. The state is now appealing that ruling.