An American military plane has crashed in northern Norway during a military exercise.
All four occupants were killed, as the Norwegian broadcaster NRK reported on Saturday, citing the police in the Norwegian province of Nordland.
The dead are said to have been American citizens.
It was initially unclear why the plane crashed.
The police announced investigations.
Norway's Prime Minister Jonas Gahr Støre expressed his condolences to the relatives and comrades of the victims.
"Our deepest sympathy goes to the families of the soldiers, loved ones and comrades in their unit," Støre wrote on Twitter.
The US Marine Corps MV-22B Osprey had been participating in a NATO military exercise dubbed "Cold Response" when it was reported missing at 6:26 p.m. Friday.
A rescue helicopter and a Norwegian military aircraft searched the area and spotted the wreckage from the air at 9:17 p.m. after receiving a distress signal.
Because of the bad weather, the rescue plane could not land.
Instead, the police and emergency services try to reach the scene of the accident by land.
30,000 soldiers, 220 aircraft and over 50 ships from NATO countries are taking part in "Cold Response", the largest military exercise under Norwegian leadership since the Cold War.