A member of the Mali Armed Forces seen patrolling the road in central Mali. AFP
In Kalumba, near the Mauritanian border, "the death toll on the friendly side is 12, including three civilians from a road construction company", the army said in a statement.
The army death toll in Sokolo, in central Mali, was six with 25 others wounded, five of them seriously.
A third attack, in centrally-located Mopti ended without casualties overnight.
Over the weekend, Mali's army said it had thwarted a new attack on a military camp in the centre of the country, two days after a deadly suicide attack in a strategic garrison town near the capital.
The Malian army has intensified its anti-jihadist operations in recent months, relying on what it describes as Russian instructors.
Despite a deteriorating security situation, the junta turned its back on France and its international partners, instead leaning on Russia to stem the threat posed by jihadists to Mali, as well as Burkina Faso and Niger.