A mystery illness has killed more than 2,000 nomads in Ethiopia’s Somali region since 2014, according to a report published Tuesday by Voice of America (VOA).

Those who have treated the ill say symptoms of the mysterious illness include bleeding from the nose and mouth, swollen limbs, and a green or yellow tint to eyes. Victims of this mystery ailment comprise a nomadic tribe of cattle herders, who roam the Ogaden Basin region, rich in oil and natural gas reserves.

Another group drawn to the Ogaden Basin region is the Chinese oil and gas firm Poly-GCL, which has surveyed the area since 2014, when the nomads began to exhibit symptoms of the illness.

The imminent construction of a pipeline by Poly-GCL in the region near Calub, Ethiopia, has riled residents, who argue the project will destroy the local environment and compromise grazing area for their cattle; they also add that they have not been consulted regarding the enterprise.

With the commercial gas venture on the horizon, the Ethiopian government has recently signed an agreement with Poly-GCL allowing for the African nation to gain 50 percent of any income from oil or gas production. As a result of the Chinese pipeline, Ethiopia will be able to export natural gas.

Despite concern from both locals and outsiders, such as Western reporters and researchers from human rights groups, Ethiopian Prime Minister Abiy Ahmed denies allegations that the oil and gas project has caused any damage to the health and environment of the region or its people.

He defends the deal with the Chinese as essential for Ethiopia’s economic growth. Ethiopia indeed looks to China for economic support.

The joint oil and gas venture between the two nations illustrates a strategic alliance between Ahmed and Chinese dictator Xi Jinping, whose Belt and Road Initiative aims to consolidate power for China across Asia, Africa, and Europe.