The bus was carrying 37 Russian tourists from Phuket International Airport to Patong when the accident occurred at about 7:30am.
The bus driver, Aroon Yaemkua, told police that he was descending the large hill southbound out of Kamala toward the coastal road when he was forced to swerve to avoid a car attempting to overtake the bus.
The bus crashed through the roadside barrier and rolled over onto its roof.
The injured Russian tourists were taken to Patong Hospital, a Kusoldharm Foundation rescue worker at the scene told the Phuket Gazette.
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