South African officials say it's a fatal case of "friendly fire" in the country's biggest wildlife park.

South Africa's parks service says a wildlife ranger was accidentally killed by a colleague who opened fire after they were charged by a buffalo in Kruger National Park on Thursday.

The parks service says the rangers, who were on an anti-poaching patrol, found cover during the confusion and were trying to shoot the buffalo to ensure their own safety.

Spokesman Reynold Thakhuli said Friday that the shooting was a case of "friendly fire" and that the ranger who shot his colleague is receiving psychological counseling. Thakhuli says police are investigating.