London Evening Standard/London

A London doctor has died in a freak accident while tackling one of the world’s most difficult rock climbing challenges.

Felix Kiernan, 28, was hit by a falling boulder dislodged by his climbing partner in the Yosemite National Park in California as they scaled the 3,000ft El Capitan rock formation.

Dr Kiernan, from Gospel Oak, was about 600 feet up when a rock measuring about 1ft by 2ft came loose and fell 150 feet before striking him. He suffered fatal injuries and was pronounced dead at the scene by park rangers.

His body was taken back down to the valley floor by helicopter while rangers accompanied his climbing partner to safety.

Dr Kiernan’s family said the pair were “extremely cautious” and experienced climbers, and stressed that his friend was not to blame. His parents, Sarah and Patrick, said they were shocked by the death of their “fantastic” and “beautiful” son, but their thoughts went out to his climbing partner and lifelong friend who was extremely upset.

Patrick Kiernan, 60, who is also a doctor, said: “Climbing was a passion of his. He was on a six-month break before he was due to start his training to be an oncologist. He had been to Thailand before the States.

“He and his climbing partner, Luke, were very experienced climbers and were extremely cautious. But it was a freak accident. Our thoughts go out to Luke, who is still in the States. The family are all here together and we are in shock.”

Dr Kiernan, who attended Manchester University before joining Barts and The London, was based at Homerton Hospital. He leaves a twin brother, Miles, who is also a doctor, and their younger sister Dorcas, 23.

Sarah Kiernan, 59, paid tribute to her son, saying: “He is going to be missed so much.” She described him as “fantastic, charming and so charismatic”. She added: “He really was a delightful person. He was handsome and so much fun. He took everything in his stride and was a real wit. He was so clever and intelligent. He was a beautiful man.”

The accident, on Sunday, was the second death at the national park over the weekend. Aleh Kalman, 19, from nearby Sacramento, was swept over a waterfall on Saturday. Some 12 to 15 deaths occur every year at Yosemite, one of America’s most famous national parks. The park draws millions of visitors from the US and around the world every year.