Thousands more Norwegians held similar musical protests in towns across the country. The protest came as survivors lined up inside the courtroom to take the witness stand and describe the bombing.
"I was spitting teeth," said Harald Foesker, who had been at work in the Ministry of Justice when the 950kg fertiliser bomb went off outside his window.
"I felt at once that this was a terror attack on the government building … I called for help but nobody answered."
He said he lost 80% of his vision and his face had to be restored afterwards, but added he was proud to live in a country that treated criminal defendants with dignity.