After receiving a report of the 11.30am accident in tambon Sob Khong, an informed source said rescuers had to use a helicopter to move the injured out of the rough terrain and take them to Maharat Nakhon Chiang Mai Hospital.
The group was reportedly in Omkoi to produce a documentary film and had also brought along a team of medical personnel to provide locals with free check-ups.
Omkoi traffic police officer Sergeant Praison Inthasoy said the 60km-long road from the district to Mo Po Ta village, where the accident took place, was a winding, one-lane dirt road in a mountainous area, which can only be accessed by four-wheel-drive vehicles. The 5km leading to this newly set up Karen village can only be accessed on foot and the area had no phone signal, the officer said.