A conservationist and veterinarian with dual French and Australian citizenship who was kidnapped last week in Chad has been released.

Chad President Mahamat Idriss Deby announced Jerome Hugonnot’s release Sunday in a post on Twitter without providing any further details.

Hugonnot who manages an oryx park on behalf of the Sahara Conservation Fund, or the SCF, was kidnapped Friday by unknown assailants.

SCF has been working for years to re-introduce into the environment a species of desert antelope known as the scimitar-horned oryx.

The reason for Hugonnot’s kidnapping or whether a ransom was paid for his release was not immediately clear.

Source: Voice of America