Three wolves shot after escaping from UK zoo

Three wolves have been shot dead after they escaped from a zoo in the UK, prompting an eight-hour search throughout the region. 

Five timber wolves escaped through a broken fence at Colchester Zoo in southeast England and were noted missing Tuesday morning, the BBC reported.

One animal returned on its own and another was shot with a tranquilizer dart and returned, but the three other wolves suffered more unfortunate fates. 

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Two of the wolves had made their way to the perimeter of the zoo and were shot and killed, while the final wolf led authorities on an eight-hour hunt, including armed officers and a helicopter while the area was cordoned off, according to the Guardian.

The final wolf was eventually located in thick underbrush and shot dead. Zoo officials have said they will conduct a full investigation into the incident. It remains unclear why the fence was broken. 

Why shoot the animals? The Colchester Zoo explained its reasoning in a statement on its website: "Unfortunately, an anesthetic dart takes 15 minutes to take effect and may not work at all in a stressed animal so two wolves that had left the perimeter of the zoo had to be shot. They are wild animals and in an unpredictable situation they would have posed a risk to the public."

Colchester Zoo, one of the largest in England, opened in 1963 and is now home to over 260 species, including numerous rare individuals.