At least 49 civilians and 15 soldiers were killed when Islamist militants attacked a military camp and a vessel in northeastern Mali on Thursday, the interim government said.
Many more were wounded, it added in a statement read on national television, noting that the death toll was provisional.
Insurgents attacked a boat carrying civilians across the flooded plains that separate the towns of Gao and Mopti during the rainy season. The vessel was traveling from Gao when it was hit.
Assailants also attacked a military camp in the Bourem Circle, an administrative subdivision of the Gao region in Mali's northeast.
Around 50 assailants were killed in response and three days of national mourning declared, the interim government said.
Mali is one of several West African countries battling a violent insurgency with links to al-Qaida and Islamic State that took root in its arid north in 2012.
Militants have gained ground, spreading across the Sahel and to coastal West African nations, despite costly international efforts to support local troops. Thousands of people have been killed and over 6 million displaced across the Sahel region south of the Sahara.
Frustrations about growing insecurity spurred two military takeovers in Mali and two in Burkina Faso since 2020 -- four of eight coups to hit West and Central Africa over the past three years.