Max Mumby/Indigo/Getty; Frankfurt Zoological Society
Prince William is grieving a friend.
The Prince of Wales, 40, issued a rare personal statement on Twitter Friday after his friend Mark Jenkins and his son were killed in a plane crash in Kenya earlier this week.
"Yesterday, I lost a friend, who dedicated his life to protecting wildlife in some of East Africa's most renowned national parks. Mark Jenkins, and his son Peter, were tragically killed when flying over Tsavo National Park while conducting an aerial patrol," William began a two-part post from his Prince of Wales account.
"Tonight, I'm thinking about Mark's wife, family and colleagues who've sadly lost a man we all loved and admired," he added, signing off "W."
Chris Jackson/Getty Prince William and Kate Middleton
William and his wife Kate Middleton are known to sign off personal social media posts with their first initials. PEOPLE confirms that the prince met Jenkins during his gap year after graduating from Eton College in 2000, and the two stayed in touch. Prince William got involved with the African wildlife conservation charity Tusk in 2005, and Jenkins followed his work there in the years that followed.
According to an obituary shared by the Frankfurt Zoological Society, Mark and Peter were conducting an aerial patrol for the David Sheldrick Wildlife Trust when the plane went down. A lifelong conservationist and veteran bush pilot, Mark previously worked for the Kenya Wildlife Service and Frankfurt Zoological Society.
"Passionate, principled, and strong-willed, Mark was never afraid to speak his mind and stand for what he believed in. He was a commanding presence and made an indelible impression wherever he went," the obituary said.
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"Those of us who worked alongside him remember him for his determination, thoughtfulness, his energy, his mischievous smile, and his deep love of wildlife and wild places," it continued. "We will miss his warmth, his hilarious stories, and his sometimes rather irreverent comments which always made us smile."
Mark is survived by his wife and son. The Mirror reports that an investigation is ongoing.