Mahamat Said Abdel Kani pleaded not guilty to charges of war crimes and crimes against humanity.

He is accused of being in charge of a police compound in the capital Bangui in 2013 where supporters of the deposed President François Bozizé were brutally tortured.

The prosecutor will rely on the evidence of 43 witnesses in the trial which is expected to last several months.

Mr Said's defence team dispute the reliability of the evidence against him.