Both sides in the fighting between the Democratic Republic of Congo's army and a Rwanda-backed militia have likely broken the rules of war by firing explosives into civilian-packed areas, Amnesty International said Monday.
More than 100 civilians were killed in the eastern DRC as a result of the indiscriminate use of ground-launched rockets in the first half of 2024, the rights group said in a new report.
Both the Congolese army and the M23 Movement, an armed group claiming to defend ethnic Tutsis, were at fault for the rise in the use of the "inherently inaccurate" weapons, it said.
Since its resurgence in late 2021, the M23 -- with the support of 3,000 to 4,000 Rwandan soldiers -- has seized vast swathes of the DRC's mineral-rich east, triggering a humanitarian crisis and displacing thousands.
Vowing to retake its lost territory, the DRC's army has retaliated in counter-offensives with the support of pro-Kinshasa militias.
In fighting between January and July 2024, "inaccurate explosive weapons with wide area effects (were) used in densely populated areas more than 150 times," the Amnesty report found.
"These attacks, which killed more than 100 civilians and wounded hundreds, violated international humanitarian law and likely constitute war crimes," it added.
Amnesty said the International Criminal Court (ICC) should consider investigating these attacks "as war crimes, with a view to bringing to justice those suspected of responsibility.
"The Congolese authorities have shown they are unwilling or unable to do so," Amnesty added.
The ICC said last year it was relaunching its probe into the conflict.
Amnesty asserted that neither the DRC nor the M23's leadership had responded to the investigation's preliminary findings, published last December.
"The M23 and Congo's army must stop bombing civilians immediately," said Amnesty International's Secretary General Agnes Callamard.
Clashes have intensified in recent weeks despite Angolan-led efforts to put a stop to the fighting.
On Saturday evening the M23 made fresh gains, taking control of the mining town of Lumbishi in South Kivu.
Home to a string of rival armed groups and ethnic so-called "self-defence" militias, the eastern DRC has been riven with conflict for the past three decades.