Chad’s former President Hissene Habre is due to go on trial in Senegal for crimes against humanity, torture and war crimes.
The trial in Dakar marks the first time one African country has prosecuted the former leader of another.
Mr Habre is accused of being responsible for the torture and murder of thousands of people during his rule from 1982 to 1990, which he denies.
The trial follows a 25-year campaign to bring him to justice.
Many of Mr Habre’s alleged victims have been calling for it since his overthrow and exile in Senegal in 1990.
In 2005 a court in Belgium issued a warrant for his arrest, claiming universal jurisdiction and, after discussions within the African Union, the AU asked Senegal to try Mr Habre “on behalf of Africa”.
Mr Habre was finally indicted in 2013 but has refused to cooperate with the special court that was set up to try him.
Landmark trial – Laeila Adjovi, BBC Africa, Dakar
This is the first time an African head of state will be tried in another African country – for torture, war crimes and crimes against humanity.
Some campaigners think it will show that Africa can hold its own leaders to account rather than rely on the International Criminal Court (ICC).
The African Union has become increasingly hostile to the ICC, believing that it has unfairly targeted Africans.
Hissene Habre could not be tried before the ICC as his alleged crimes were committed before it was established in 2002, but the special court established jointly by Senegal and the African Union in Dakar could set a template for future trials.
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