Emergency services have found 11 bodies after a helicopter crashed off the west coast of Norway, a rescue official told Norwegian broadcaster NRK.

A search for the remaining two passengers was ongoing, a spokesman from the Rescue Coordination Centre for Southern Norway told NRK on Friday, adding that among the 13 passengers were one British and one Italian national. The others were Norwegians.

Police officials told regional news outlets that all on board, including those missing, were presumed dead.

Witnesses told the broadcaster that the helicopter was on its way inland from the North Sea when it got into difficulty.

NRK said the aircraft dropped 640 metres in the 10 seconds preceding the crash.

The crashed helicopter is a Eurocopter model, according to the Norwegian Civil Aviation Authority, which imposed a flying ban in the aftermath of the crash.

"There were challenges with this kind of helicopter model in 2012, when errors in the main gearbox were identified," the authority said in a statement.

"That model received flying restrictions in 2012 and 2013."

Another Eurocopter model operated by the Air Ambulance service crashed in 2014 near the town of Sollihogda, killing two crew members onboard

Eurocopter is made by a subsidiary of planemaker Airbus.

Source: Reuters And Al Jazeera