Four endangered Eld's deers were photographed for the first time in five years by cameras deployed in a wildlife sanctuary in Northeast Cambodia's Kratie province, according to the World Wildlife Fund (WWF)-Cambodia's press statement on Saturday.

The cameras were placed in the Sambor Wildlife Sanctuary located in the Mekong flooded forest landscape, the statement said, adding that the Eld's deer is listed as endangered in both Cambodia's Forestry Law and on the International Union for Conservation of Nature (IUCN) Red List.

Conservationists are thrilled to see the rare images of three adult females and one juvenile Eld's deer roaming the sanctuary, as they examined this week 1,710 photographs produced between August and September by the cameras that were deployed at different locations in the sanctuary with a total area of 50,093 hectares.

"We are very excited about this discovery," said Eam Sam Un, biodiversity research and monitoring manager with the WWF.

The camera trapping survey efforts were conducted jointly by researchers and rangers from the Kratie's Provincial Department of Environment, Community Forestry, and WWF staff, the statement said.

WWF's scientists described the camera trap event as a significant discovery for conservation in the Mekong landscape.

"The photographs provide evidence that our conservation efforts are paying off, raising hopes for the protection of the animal in the country and region," said Seng Teak, WWF country director.

Aside from the Eld's deers, the photographs also documented the presence of red muntjac, wild pig, small indian civet, common palm civet, as well as large bird species such as the endangered green peafowl and vulnerable lesser adjutant.

A report on threatened species published by IUCN in 2015 showed the population of the Eld's deer has scattered across the globe with an estimate of less than 700 individuals, and with a small subpopulation remaining in Cambodia's protected forests.

The WWF has been working closely with the Cambodian government at all levels to support the management of the Sambor Wildlife Sanctuary, where habitat loss and poaching for meat and trade are among major known threats to the species' survival, the statement said.