The sets of remains were discovered within some caves in Pack U district of Luangprabang province and Muang Nga district of Oudomxay province from January to June 2018.

Senior Lieutenant Colonel Nguyen The Giang from the Search and Collection Team says according to local people, Vietnamese soldiers used the caves as a base to conduct their fighting from during the past war.

The sets of remains are scheduled to be repatriated on June 14. A memorial service and funeral for the unknown martyrs will take place at Tong Khao Cemetery in Dien Bien Phu City on June 15.