Two female brown bears have been shot and killed at Whipsnade Zoo in Bedfordshire after they escaped from their enclosure when strong winds toppled a tree. The zoo’s chief curator, Malcolm Fitzpatrick, said in a statement that the tree fell in such a way that it formed a “bridge” between the brown bears’ pen and the fence of the neighbouring wild boar enclosure. The two bears crossed into the enclosure, where they attacked a male boar. Fitzpatrick said the zookeepers had no choice but to euthanise the bears over concerns of an “immediate threat to human life”. “As brown bears are strong and dangerous predators, our first priority is safety – we must quickly make decisions informed by our experience and expertise to protect our people, guests and our other animals,” he said. “No one wants to be the one to make that call, but when there’s an immediate threat to human life, the decision is made for you. The colleagues involved today have experienced the dreadful situation that every vet and keeper thoroughly trains for, but hopes will never come to pass. I ask you to support them in the coming weeks as they come to terms with today’s events.” Fitzpatrick said it would not have been practical to use a tranquilliser to sedate the bears because it would have taken up to 20 minutes to work, “during which the animals can become unpredictable and aggressive as adrenaline is coursing through them. We had to intervene immediately to ensure the bears didn’t get out of the boar enclosure, which has a low fence.” A third bear that did not leave the enclosure was called to her indoor den and secured. Vets are treating the injured boar and the fallen tree has been removed. Fitzpatrick has promised a full investigation into the incident. “I’m devastated by the outcome of this morning’s incident, but I’m confident that our actions prevented any further loss of life,” he said.