The International Criminal Court said on Thursday that it had released a former militia leader in the Central African Republic and is dropping all charges against him.
Maxime Mokom had faced charges of war crimes and crimes against humanity over alleged atrocities committed against Muslim civilians in the CAR by his self-proclaimed self-defence militias in 2013 and 2014.
The ICC's prosecutor Karim Khan said his office had concluded there were "no longer any reasonable prospects of conviction even if the charges were confirmed".
He said the decision was taken after considering all the evidence and "changed circumstances regarding the availability of witnesses".
Mokom, who was released on Tuesday, has denied all involvement in the bloodshed, telling ICC judges in August he was "dedicated to the search for peace".
The charges Mokom had faced included directing attacks against the civilian population, murder, rape and pillage.
The CAR was plunged into bloody sectarian conflict in 2013 after Seleka rebels, a coalition of armed groups mainly composed of Muslims, ousted president Francois Bozize in early 2013.
Mokom's militias, the "anti-Balaka", formed in reaction to the takeover of the capital, Bangui, by the Seleka.
Anti-Balaka attacks continued on Muslim civilians even after Seleka forces retreated from Bangui, until at least December 2014.
The CAR remains troubled and peace agreements signed in 2017 and 2019 have not been respected on the ground.
Legal and ethical responsibilities
Khan said his office reserved the right to request a new arrest warrant if more evidence came to light and addressed those affected by the atrocities in the country.
"I am very conscious that this news may be unwelcome to many survivors and their families," he said. "I hope many will understand my legal and ethical responsibilities to be guided by the law and the evidence."
The ICC issued an arrest warrant for Mokom in 2018 and he was finally handed over by Chadian authorities last year.
Set up in 2002, the ICC is the world's only independent tribunal capable of prosecuting those accused of the world's worst crimes.