A Sumatran tiger born in London Zoo for the first time in 17 years has drowned after falling into a pond.
London Zoo said the newborn died in the early hours of Saturday morning and keepers believe first-time mum, Melati, may have carried the three-week-old cub into the outdoor paddock, where it fell into the pond and drowned.
The zoo said it was "heartbroken" and "would do anything to turn back the clock".
Melati was said to be a very nervous tiger that responds best to routine and took time to settle into her new home. Zookeepers were worried that any changes to her environment could cause her to react badly and potentially injure or abandon the cub.
In a statement, London Zoo said: "The decision to allow her continued full access to the outdoor paddock and pond as normal was carefully considered and thought to be in the best interests of Melati and the cub."
Curator Malcolm Fitzpatrick, explained: "We're heartbroken by what's happened. We didn't want to put her on edge by changing her surroundings or routines, in case she abandoned or attacked the cub. At the time we thought it was in the best interests of Melati and her cub to allow her continued access to the full enclosure as normal.
The Zoo is carrying out a full review of the circumstances around the incident.
London Zoo celebrated the birth of the unnamed cub October after Sumatran tiger Melati 105-day pregnancy.
Melati gave birth in just six minutes and the sex of the cub was to be known in mid-November.
The newborn was the "grandchild" of the last tiger cub born at the zoo, Hari, who is Melati's father.
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