Two people were killed Tuesday when a Norwegian air ambulance crashed north-west of Oslo, the operator of the helicopter and police said.
A third person who was on board was transported to Oslo University Hospital, but the extent of that person's injuries were not known, dpa reported.
Witnesses quoted by local media said the helicopter hit a power line before crashing.
The helicopter had been dispatched to an accident involving a truck that had overturned in slippery conditions near a road tunnel at Sollighoda, 30 kilometres west of Oslo.