The women, Karin Bowerman, 27, of Wisconsin, and Cathy Juynh, 26, of Ontario, Canada, died days apart while visiting Nha Trang, Vietnam, this summer. The women's families have been awaiting autopsy results to explain what killed the women. Speculation ranged from alcohol poisoning to insecticides.
But Tuoi Tre News quoted a police official who said toxicology reports show no toxins in the women's systems. The cause of both deaths was a buildup of fluid in the brain.
The women checked in to a military hospital with symptoms that included shortness of breath and vomiting, but were conscious at the time, before their conditions worsened and they died, CNN reported.
Police have not released the full autopsy results.