They will be taken to the Dong Nai Culture and Nature Reserve in Dong Nai Province near Ho Chi Minh City.

The snakes were discovered two months ago by the workers at the foot of Cam (Forbidden) Mountain in An Giang Province in the Mekong Delta, 300 kilometers (190 miles) to the west.

They captured the snakes, which measure four meters (13 feet) long and weigh 18 kilograms (40 pounds) each.

A caretaker said the snakes have got thinner after not eating for many days, but they are still very strong. They were put in a net by experts from a nearby snake farm, before being transported to Dong Nai.

The king cobra is the world's longest venomous snake, with the largest known individual measuring nearly six meters, and endemic to forests from India through Southeast Asia.

Local authorities had planned to release the snakes back in Cam Mountain in unspoiled habitats far away from human habitation.

Bu they later decided to put them in a conservation area with microchips implanted in them. The chips will have a life span of 20 years and allow experts to keep track of the snakes and monitor their health.

Lu Cam Khuong, deputy director of An Giang's agriculture department, said the plan changed because the environment in the mountain, the tallest in the Mekong Delta, was not secluded enough. The place, which was once home to a wide range of wild animals like deer, tigers, leopards, and king cobras, now gets many visitors. Khuong said putting the snakes on the mountain would threaten the well-being of both snakes and humans.

The king cobra is threatened by habitat destruction and listed as vulnerable by the International Union for Conservation of Nature since 2010.

In Vietnam, it is classified as an animal with a high extinction risk and their exploitation for commercial purposes is prohibited.