The aircraft took off from Lamidanda Airport, 162 km (101 miles) east of Kathmandu and was heading to the capital.

Ram Prasad Neupane, head of the civil aviation authority, said emergency services had been alerted and a search and rescue effort was under way.

There were 19 passengers and three crew members on board the plane belonging to small domestic airline Tara Air.

Two army helicopters have flown to the remote area to search for the Twin Otter plane.

Reports from Katmandu's Tribhuwan International Airport suggest at least one passenger was believed to be a foreign national but their identity and nationality is not known.

The remaining 18 passengers were all Nepali citizens who were returning from a pilgrimage to a Hindu temple.

Aviation accidents are not uncommon in mountainous Nepal.

In August, a plane heading for the Everest region crashed in bad weather killing all 14 people on board, including four Americans, a Japanese national and a British national.