Bensouda, a former Gambian justice minister, takes over from Argentinian Luis Moreno-Ocampo, who is stepping down after a nine-year term. During that time, Moreno-Ocampo became known as the ICC's public face.
Bensouda is the first woman, and the first African, to hold the chief prosecutor position.
The BBC said Bensouda will be tasked with bringing Libya's Saif al-Islam Gaddafi to justice, and will also oversee the trial of the Ivory Coast's ex-president, Laurent Gbagbo.
Bensouda, a former senior legal adviser at the International Criminal Tribunal for Rwanda, has spent the last eight years at the Hague-based court, serving as Moreno-Ocampo's deputy chief prosecutor.
She has a reputation for "controlled calm and sensitivity," the BBC reported.
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So far, only one person has been convicted by the court: Congolese warlord Thomas Lubanga, who in March was found guilty of recruiting and deploying child soldiers.
The ICC has been criticized for the fact that all suspects wanted or on trial at the court are African.
According to the BBC, the African Union (AU) lobbied hard for Bensouda to be named chief prosecutor, after having repeatedly accused Moreno-Ocampo of targeting Africa.
Bensouda, addressing the court, said she was “humbled” by her appointment, and promised to continue pursuing all cases that fall under the court’s jurisdiction, the Associated Press reported.
“As I speak, massive crimes continue to be committed in Darfur [Sudan]; Joseph Kony and the Lord’s Resistance Army’s acts of violence continue unabated in central Africa,” she said.
“Nothing short of arresting all those against whom warrants have been issued will ensure that justice is done for millions of victims of the crimes committed by these fugitives.”
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