Three Tunisian soldiers were killed in an explosion set off by "terrorists" on Monday near Mount Sammama, a hideout for jihadists at war with the authorities, the defence ministry said.

Defence ministry spokesman Belhassen Oueslati told Mosaique Radio FM that "terrorist elements launched an attack with a large quantity of explosives on a military patrol providing security for workers" tarring a road.

Three soldiers were killed and seven wounded, he said, adding that two militants were believed to have been killed by army fire and their bodies removed.

Mosaique FM radio said earlier that a blast hit a military vehicle as soldiers combed an area near the town of Kasserine.

The violence came on the same day a new unity government took office in Tunisia with security among its top priorities.

Jihadist attacks in Tunisia have cost dozens of lives among security forces as well as civilians, and 59 foreign tourists were also killed in 2015.

Tunisian forces have been tracking jihadists mainly in the mountainous regions of Chaambi and Sammama, southwest of the capital Tunis.

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