Very weird. Some kind of cult thing? Does Vietnam have a beef with anyone?
Later article says:
Investigators said the bodies were foaming at the mouth, an officer from the Lumpini police station said on condition of anonymity because he wasn’t authorized to release information.
Six people are found dead in a hotel in downtown Bangkok, with poisoning a possibility
https://apnews.com/article/thailand-bangkok-hotel-deaths-fef64b28304c8dcb201bd40c8dd09862
Suicide pact?
More news: looks like it was about money after all.