Dozens of people were feared killed in remote parts of north-western Nepal after the areas were hit by a freak snow storm, officials said on Tuesday.

The casualties were reported in the remote north-western mountainous district of Dolpa, about 450 kilometres north-west of the Nepalese capital, on Monday.

"We have reports that at least 16 people died and about a hundred others were blinded by a freak snow storm and blizzard," Home Ministry spokesperson Baman Prasad Neupane told Deutsche Presse-Agentur dpa.

The snow storm is said to have hit a mountainous area where hundreds of people had gathered to collect an herb locally known as Yarshagumba, which is thought to increase sex drive.

Other reports in the Nepalese capital said up to 1 500 people were stranded in heavy snows. However, the Home Ministry said it could not immediately confirm the report.

"The area is very remote and we are still verifying information received from local government officers," Neupane said.

"We have launched a rescue mission and helicopters are on their way and the full extent of the situation is expected to become clear later."

The rescue mission is expected to proceed slowly due to continuing bad weather in the area and lack of road access in the district.