The two-seater Savannah S aircraft operated by African Parks Network conservation group went down during a surveillance flight over Chad's southern Zakouma region, it said in a statement.

The South African pilot and an official from Chad's Environment Ministry died.

"The Civil Aviation Authority regrets to confirm that, according to information received, the two occupants tragically lost their lives in the accident," it said, adding that an investigation has been launched.

--Reuters--