A large explosion has hit near government headquarters in the Norwegian capital Oslo.
At least one person was killed in the city centre blast, national broadcaster NRK reports.
The offices of Norwegian Prime Minister Jens Stoltenberg were damaged extensively but he was reportedly unharmed.
At least eight people were injured, local media said. No-one has said they were behind the explosion.
Television footage from the scene showed rubble and glass from shattered windows in the streets - smoke was around some buildings. The wreckage of at least one car was in street.
All roads into the city centre have been closed, said the NRK, and security officials evacuated people from the area, fearing another blast.