A bus carrying Tunisian tourists crashed in the mountains in the country's north on Sunday, killing 22 people and injuring 21, the interior ministry said.  

The bus was travelling through the Ain Snoussi region when it plunged over a cliff, the ministry said. 

The vehicle had "fallen into a ravine after crashing through an iron barrier," it said on its Facebook page.

All those aboard were Tunisians, said the tourism ministry. The injured were transferred to nearby hospitals, the interior ministry said. 

The bus had been heading from Tunis towards the picturesque mountain town of Ain Draham, a popular autumn destination for tourists.

The World Health Organization in 2015 said Tunisia had the second worst traffic death rate per capita in North Africa, behind war-torn Libya.

Experts blamed run-down roads, reckless driving, and poor vehicle maintenance for a rise in accidents the following year.

The authorities recognize the scale of the problem but have said the country's security challenges, including jihadist attacks, have kept them from giving it more attention.