The regional bus, which was carrying 43 people and belonged to a private local company, veered off a winding road after the driver failed to manoeuvre a sharp turn and crashed at the bottom of a ravine, the interior ministry said.

Local media showed images of an overturned, crumpled bus with smashed windows at the foot of a hill.

Health ministry spokesman Chokri Nafti said the crash on Sunday morning left 18 people injured. Some were rushed to the nearby Amdoun and Beja hospitals, while the more seriously injured were transported to specialised hospitals in Tunis.

When it crashed, the vehicle was headed 185 kilometres west from capital Tunis to Ain Draham, a beautiful local tourist spot renowned for its mountainous reliefs on the border with Algeria.

Ain Draham is located at an altitude of 800 metres on the slopes of the Djebel Bir, one of the Kroumirie mountains.

Prime Minister Youssef Chahed interrupted a visit to the south of the North African country to return to the seat of government in Kasbah where a crisis centre has been set up.

Australian Associated Press