Human Rights Watch on Wednesday accused an Islamist armed group and an ethnic militia of killing at least 45 civilians in separate attacks in January in central Mali, a region plagued by communal violence.
Fighters from the Al-Qaeda-linked coalition Group for the Support of Islam and Muslims (GSIM) "killed at least 32 civilians, including three children, and set fire to over 350 homes" in attacks on the villages of Ogota and Ouembe on January 27, HRW said.
At the beginning of January, Dozo militiamen -- traditional hunters consisting mainly of ethnic Bambara -- had killed 13 civilians and abducted 24 others in the villages of Boura and Kalala, which is predominantly ethnic-Fulani, according to HRW.
"These attacks occurred amid recurrent tit-for-tat killings and communal violence in central Mali," the NGO added.
HRW said January's attacks were "apparent war crimes" and called on the Malian authorities to "urgently investigate the abuses".
Mali has since 2012 been plunged into turmoil by independence and Salafist insurgencies in the north.
The centre of the country has become a hotbed of violence since 2015, with the emergence of jihadist groups led in particular by the firebrand Fulani preacher Amadou Koufa, who has largely recruited from among his own community.
The violence has spilled over into neighbouring Burkina Faso and Niger
Clashes have increased between the Fulani, who are mainly herders, and the Bambara and Dogon, largely farmers, leading to the formation of ethnic self-defence groups.
The deteriorated security context, remote locations and a lack of reliable information mean that attacks often take a long time to confirm.
The Malian armed forces have stepped up operations in the centre of the country in recent months, along with Russian paramilitary group Wagner.
They are also accused of numerous abuses against civilians, particularly the Fulani.
"The Malian transitional government's failure to hold Islamist armed groups and ethnic militias to account only emboldens abusive forces to commit further atrocities," said Ilaria Allegrozzi, senior Sahel researcher at HRW.