OSLO, Norway - A Norwegian court on Friday ordered a new psychiatric evaluation of confessed mass killer Anders Behring Breivik, after an earlier report found him legally insane.

Judge Wenche Elizabeth Arntzen said in Oslo that the new evaluation is necessary considering widespread criticism of the initial findings, which suggested Breivik should be sent to psychiatric care instead of prison.

The 32-year-old Norwegian has confessed to a bomb and shooting spree on July 22 that killed 77 people and traumatized the peaceful Scandinavian country.

Breivik denies criminal guilt, saying he's a commander of a resistance movement aiming to overthrow European governments and replace them with "patriotic" regimes that would deport Muslim immigrants.

Investigators have found no sign of such a movement and say Breivik most likely plotted and carried out the attacks on his own.

Arntzen said two Norwegian psychiatrists -- Agnar Aspaas and Terje Toerrisen -- had been appointed for the new evaluation.

The first court-ordered assessment found Breivik was psychotic during the attacks, which would make him mentally unfit to be convicted and imprisoned for the country's worst peacetime massacre.

Prosecutors said that report, submitted in November, describes Breivik as a paranoid schizophrenic living in a "delusional universe."

That conclusion drew criticism from many outside experts who questioned whether someone who is suffering from a grave mental illness could carry out such a well-planned attack.

Arntzen also noted that staff at Ila prison in Oslo, where Breivik is being held in pretrial detention, say they haven't observed any signs suggesting he is psychotic.

"These circumstances point toward letting independent experts conduct a new evaluation of the suspect's accountability," Arntzen said.

Asked what would happen if the new assessment conflicts with the first one, Arntzen said both reports would be considered by the court when the trial starts in April.

It was unclear whether Breivik would co-operate with the psychiatrists. He rejected the need for a new evaluation in a motion filed to the court by his defence lawyer, Geir Lippestad.

Breivik has told investigators he set off the fertilizer bomb that ripped through Oslo's government district on July 22, killing eight people. He then opened fire at the summer camp of the governing Labor Party's youth wing on the island of Utoya, where sixty-nine people were killed before Breivik surrendered to a SWAT team.