The story writes Christians are murdered because of their membership in a church. Readers should be aware that the yellow skin Vietnamese despise the dark skin Montagnards as an inferior race. Montagnards vigorously supported America during the Vietnam war. The communists remember that and see that as reason enough to kill Montagnards. Religion may play a role, but it’s not the only one here.
Your tagline gives away your off-base thinking.
Montagnards ARE a different race from the Vietnamese. The Montagnards, like the Champa or the Khmer in Cambodia are a Mon-Khmer people who are related to the Polynesian-Malay peoples. The Vietnamese were pushed down from Southern China by the Han Chinese in the 7th - 10th centuries and pushed out or assimilated the Montagnards.