SKIEN, Norway, Jan 10 (Reuters) - Mass murderer Anders Behring Breivik gave a Nazi salute on Tuesday to a high-security court where Norway is appealing a ruling that it has violated his human rights by keeping him in strict isolation.
Breivik, in a black suit and tie and sporting a beard he has grown in the past year, made the defiant gesture as he entered the courtroom at the start of the Jan. 10-18 hearing about his detention since he massacred 77 people in 2011.
Judge Oeystein Hermansen told him the salute was insulting and should not be repeated.
Breivik, 37, made a similar salute at the start of the lower court hearing last year where the judge agreed with him that his near-isolation in jail violated a European Convention on Human Rights ban on "inhuman and degrading treatment."
Launching the state's appeal, Attorney General Fredrik Sejersted defended the draconian measures, including hundreds of strip searches and no contact with other inmates, as fully justified for an unrepentant far-right extremist.
"There is no human rights violation," Sejersted said.
"He has not broken down, he has not expressed remorse, he is proud of what he has done," he told the court, saying Breivik seemed ever more convinced of his extreme right-wing ideology.
On July 22, 2011, Breivik killed eight people with a car bomb outside the prime minister's office in Oslo and then gunned down 69 others on an island near the capital, many of them teenagers attending a youth camp of Norway's then-ruling Labour Party.
Last year, lower court judge Helen Andenaes Sekulic ruled that Breivik was wrongly kept in a "locked world" for 22-23 hours a day, even though it comprised the apparent comfort of a three-room cell with a training room, television and newspapers.
The appeal is being heard in a converted gym at Skien jail where Breivik is serving Norway's longest sentence - 21 years with the possibility of an extension. Breivik's only contacts are lawyers and professionals such as guards and health workers.
During his last court appearance, Breivik often complained of microwaved food and cold coffee. His mother was the only family member who wanted to visit him, hugging him shortly before she died of cancer in 2013.
Breivik will address the court on Thursday.
In recent months there has been some slight easing of Breivik's detention conditions. His lawyer has been allowed to talk to him from between bars rather than through a glass wall.
Along with the Norwegian state's appeal, the court's week-long session will also consider Breivik's separate complaint that prison censorship of his letters has violated his right to a private life and correspondence.
The state says the censorship is necessary to prevent him from inciting violence.
The same lower court that upheld Breivik's human rights complaint last year turned down this separate complaint about his private life, which he also based on the European Convention on Human Rights.