Military personnel "engaged with a group of armed individuals in the Kadialock area", the armed forces said in a press release.

The incident occurred on Wednesday, and "an initial report indicates that one soldier was killed and six others were wounded", the statement said, adding that some of the assailants had been killed.

The army said it was continuing operations to "combat the cultivation of cannabis, hunt down all armed groups and secure the local populations and their property".

Casamance, Senegal's southernmost region, is almost separated from the rest of the country by the tiny state of The Gambia, with a distinct culture and language stemming from its past as a Portuguese colony.

Officials accuse rebels in the region of illicit trafficking of cannabis and wood, and of seeking refuge in The Gambia or in Guinea-Bissau to the south.

Casamance has hosted one of the longest ongoing conflicts in Africa since armed separatists withdrew to the bush after protests in December 1982.

Having claimed thousands of lives and devastated the economy, the conflict has persisted but on a much-diminished level in recent years.

In February, separatists and the Senegalese authorities signed a peace accord following their first public talks since the government was appointed in March last year.