Protecting wildlife in Kenya connects Prince William and ranger Mark Jenkins, the British prince and the game warden have been friends for many years. William is saddened and dismayed by the news of the Jenkins plane crash in Tsavo National Park.

Prince William has taken to social media to mourn a “close friend” who died with his son in a plane crash in Kenya. Mark Jenkins, a ranger, died when his light plane crashed over Tsavo National Park, according to media reports. The men are said to have just tried to drive cows, camels and goats out of the park. Nothing is currently known about the cause of the accident.

The Prince of Wales is said to have learned of the tragedy while he was about to wrap up the aftermath of the release of the first part of the Netflix documentary Harry

Prince William first met Jenkins, a game warden, in 2001 when he spent three and a half months in Africa learning about the wildlife and environment, according to The Telegraph. The two men are said to have become friends and had apparently met a few times since then.

Among other things, William is a patron of the Tusk Trust, a wildlife conservation charity, and founded United for Wildlife, an organization dedicated to protecting endangered species from the illegal trade. William proposed to his now-wife, Princess Kate, in Kenya in 2010.