For the first time, Norway has allowed the media inside a government building ravaged by a car bomb that killed eight people July 22.
Footage from Norwegian broadcaster NRK on Tuesday showed a jumble of shattered glass and damaged furniture in the Justice Ministry's offices on the seventh floor.
The ceiling of a conference room was ripped open. Crumpled blinds dangled from windows whose frames were blown apart.
NRK says three of the ministry's employees died in the explosion.
It says the prime minister's office on the 15th floor was largely unscathed. He wasn't in the building at the time of the blast.
A right-wing extremist diagnosed as psychotic has confessed to the bombing and to a subsequent shooting spree at summer camp that killed 69 people.