Updated

Red Cross officials in Central African Republic say they've retrieved 13 bodies from a mass grave found in the capital last week.

Antoine Mbao-Bogo, president of the local Red Cross, confirmed Monday that the bodies had been removed from a military base that was used by Muslim rebels during their 10-month rule.

Prosecutor Ghislain Gresenguet said an investigation was underway after African peacekeepers found the grave last Wednesday.

The Muslim rebels, known as Seleka, were blamed for scores of human rights abuses during their time in power. A Christian militia that arose in opposition to the Seleka fighters also has been blamed for atrocities.

The death toll from Central African Republic's crisis is unknown though more than 1,000 died in several days in December alone.