The landlocked Sahel state is in the grip of a seven-year-old insurgency that has claimed more than 2,000 lives and forced some 1.9 million people to leave their homes.

The fighting has been concentrated in the north and east, led by jihadists suspected to have links with Al-Qaeda or the Islamic State group.

The army announced that on Sunday troops launched a counter-offensive after rebel harassment around the northern town of Sebba.

Two rebel bases were dismantled and several clashes took place, leaving "at least 18" dead, as well as one soldier, a statement said.

Also on Sunday, special forces backed by the air force laid assault to a "major terrorist base" near Soam in the east.

"The base was totally destroyed and at least 10 terrorists were neutralised," the statement said, meaning they were killed.

"Others fled and are now being pursued by deployed units," it added.

Weapons, vehicles and communication equipment were recovered, according to the army, which urged people to "strengthen cooperation with the defence and security forces by informing on terrorists who try to melt into their midst".

With more than 40 percent of the country outside government control, Burkina's ruling junta, which seized power in January, has declared the fight against the raging insurgency a top priority.