Kasserine - Three Tunisian soldiers were killed in a "terrorist attack" on Monday near Mount Sammama, a hideout for jihadists at war with the authorities, security sources said.
The attack left six other soldiers wounded, without giving further details.
Defence ministry spokesperson Belhassen Oueslati told Al-Wataniya television that explosives were used in the attack and that "at least two terrorists" were also wounded.
Clashes between security forces and militants continuing, the private channel said.
Mosaique FM radio said earlier that the soldiers were killed when a blast hit their vehicle as they 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.