AFP 
 
Kathmandu, May 30: At least 16 Nepalese villagers died in a massive snowstorm while collecting a valuable health supplement known as 'Himalayan Viagra,' police said on Tuesday.   

"Sixteen people were killed after heavy snowfall Monday night covered their camp," a police officer said from Dolpa district.   

The villagers had ventured into the remote mountainous district 240 kilometres northwest of Kathmandu to collect yarshagumba (cordyceps sinensis).   

"The site where the accident happened is very rugged and is a four-day walk from Dunai (district headquarters) so police have yet to reach the site," the officer said.   

Yarshagumba, which in Tibetan means "summer plant, winter insect," is only found in meadows above 3,500 metres and forms when a parasitic fungus lodges itself in caterpillars and slowly kills them.   

It has been highly valued as a health tonic and aphrodisiac in traditional Chinese medicine for centuries and can fetch up to 3,000 dollars a kilogram -- a small fortune in impoverished Nepal.   

Thousands of villagers in remote Himalayan areas leave their homes to collect the tonic during the harvesting season in May and June.