A tourist bus crashed at the border town of Koh Kong on Tuesday killing two and wounded 44 others including three US nationals.
A 22-year-old Russian tourist died immediately at the scene.
"The second person died today," Koh Kong traffic police chief Ouk Sopha told VOA Khmer on Wednesday.
Authorities said the bus was struck by a punctured tyre, shortly after crossing Tatai bridge; some 20 kilometers from provincial town of Koh Kong.
The foreign tourists are Swedish, Finnish, Thai, British, Austrian, Spanish, Russian, Japanese and American.
"They finished their visit in Cambodia and were on their way to Thailand," said Ouk Sopha.
Six Cambodians were also among the injured. The victims were evacuated to a provincial hospital, but later were sent to a hospital in Thailand’s Trat province. Only six, including two US citizens, remain in Cambodia.
“The U.S. Embassy has been closely monitoring the accident and has offered consular assistance,” said Sean McIntosh, spokesman for the US Embassy in Phnom Penh.