Light illuminates Mount Everest during sunset in Solukhumbu District also known as the Everest region. File picture: Navesh Chitrakar/Reuters

Kathmandu - Sherpa guides have collected four bodies and 11 tons of trash from Mount Everest in a month-long clean-up campaign, a tourism official said on Friday.

A group of 12 Sherpa guides retrieved four bodies, dozens of oxygen cylinders as well as discarded cans, ropes, tents and wrappers from several camps on the 8,848-metre peak, said Dandu Raj Ghimire, director general of Nepal's Department of Tourism.

"The Sherpas segregated the waste at the base camp. Only recyclable waste was brought to Kathmandu," Ghimire said. The four bodies, which are yet to be identified, were handed over to forensic experts at a hospital in the capital.

Officials on Wednesday handed the trash from Everest to a recycling company in Kathmandu, he said.

During the commercial expeditions on Everest in spring season, mountain guides set up camps and ferry supplies from the base camp to higher camps.

The government rule requires each climber to bring back at least 8 kilograms of trash, but it's not widely implemented due to weak regulatory oversight.

While about 5 000 people have successfully reached the top of Everest, more than 300 have died in their attempts.

Deaths spiked during this year's April-May climbing season amid concerns of overcrowding, with 11 people losing their lives.