The International Criminal Court on Wednesday opened a war crimes probe on Mali, where French troops are fighting Islamist rebels who have been occupying half the country since April last year.
"Different armed groups have caused havoc and human suffering through a range of alleged acts of extreme violence," the Hague-based court's chief prosecutor Fatou Bensouda said in a statement.
"I have determined that some of these deeds of brutality and destruction may constitute war crimes."
Bensouda in July last year ordered a preliminary probe into reports of terrifying atrocities committed in Mali to see if the criteria for a fuller investigation were met.
She said her office believed there were sufficient grounds for "further action" and identified potential cases of atrocities in the impoverished west African state, which has effectively been split in two by the conflict.
Islamists last March took advantage of a short-lived coup in Bamako and a rebellion by Tuareg separatists in the north to seize half the country.
So far 144,500 refugees have fled the unrest to neighbouring Mauritania, Niger, Burkina Faso and Algeria, UN humanitarian agencies said Tuesday, while another 230,000 are internally displaced.