China handed over the remains of U.S. pilots who supported the Chinese Army during World War II to representatives from the United States at a ceremony held at Jianchuan Museum in Chengdu in southwest China's Sichuan Province, on Thursday.

The remains are believed to belong to pilots tasked with transporting goods to southwest China along the famous WWII air route "Hump."

The remains, as well as parts of a United States Army C-87 transportation airplane, were found at the top of a mountain in Bomi Country, Tibet, in August 2015.

The remains will be taken back to the United States where they will undergo DNA tests, said Raymond Greene, consul general of the American Consulate General at Chengdu.

The C-87 plane and remains of five U.S pilots were first found by locals in September 1993, but the majority of the wreckage remained on the glacier.

According to official files, a C-87 plane with five U.S. pilots went missing on the return route from Kunming, Yunnan Province.

The "Hump" route, which began in the southern Indian state of Assam, passed over the Himalayas to Sichuan. It was established in 1942 and closed in 1945.

It served as a crucial channel in China's, then weak, logistic system. A total of 650,000 tonnes of goods were transported via the route.

As a major airborne passage, the "Hump" route saw the loss of more than 500 planes and the lives of more than 1,500 U.S. and Chinese pilots.