OSLO (AFP) - Over half the parents of the victims of Norwegian mass killer Anders Behring Breivik remain too traumatised to return to full-time work, a study showed on Wednesday as Norway marked the fourth anniversary of the attacks.
The study, which surveyed 86 parents of the 69 people killed on July 22, 2011, on the island of Utoya - where they were attending a Labour Party youth camp - found that two thirds suffered from post-traumatic stress reactions, including impaired concentration, memory or sleep.
Fifty-one per cent of the parents were still either on partial or full leave from work.
The results, compiled 40 months after the attacks, came as no surprise, according to one of the study's authors, professor Kari Dyregrov at the Bergen Centre for Crisis Psychology.
"These are parents who lost their children, some having even been in contact with them while the perpetrator of the attacks roamed the island," he told AFP.
A third of the mothers and fathers surveyed were in contact with their children by telephone or through text messaging at the time of the shooting.
Ten mothers and nine fathers had spoken on the phone with their children just before they were killed.
"It is an extremely heavy burden to bear, especially as they have been subjected to the media's attention on a daily basis," Dyregrov said.
"Within one year, there were the attacks, the trial, the inquiry commissions... which made them delay their grieving. It had to wait. They didn't have enough energy or focus."
A large majority of parents (89 per cent of mothers and 85 per cent of fathers) attended the 2012 trial, at which Breivik was handed a 21-year prison sentence, which could be extended indefinitely.
On Wednesday, an anti-extremism exhibition was inaugurated in Oslo, in the government complex that Breivik unsuccessfully tried to blow up with a massive car bomb on the morning of his rampage.
Prime Minister Erna Solberg said the purpose of the display was to "spread knowledge in order to prevent hatred, violence and terrorism."