A group of rare warty piglets and their mother have been eaten alive by their father at Bristol Zoo.
Manilla arrived at the zoo in July 2014 and was followed two months later by Elvis.
At the time, assistant curator of mammals Lynsey Bugg said: "We hope the 'King' takes a shining to Manilla and the two become proud parents in the future."
But tragedy struck when Manilla recently gave birth, and Elvis killed his entire family.
A source told the Bristol Post: "On the day the female gave birth to piglets the male immediately ate them all, and then also attacked the mother by eating her rear end. She was so badly injured she had to be put down.
"This meant the loss of a family of rare warty pigs that could have been avoided by keeping the male separate."
But Bristol Zoo says it was not aware that Manilla was pregnant, and that the situation was "unavoidable".
A spokeswoman for the zoo said: "Female warty pig Manilla arrived with us at the beginning of July last year.
"In November she showed some subtle changes to her behaviour and keepers alerted our in-house vet team.
"She showed no physical signs of being pregnant and, as she had not been with a male between July and October, she was well outside the known birth window for this species.
Only 200 Visayan warty pigs are thought to be left in their native habitat in the Philippines – making them the rarest of all wild pigs.
The decline of the species - almost to the point of extinction - is blamed on habitat loss and hunting.
According to the Mirror, there was also recently another animal death at the zoo, which saw a golden-headed lion tamarin monkey escape fall into the lake surrounding its enclosure, before it got stuck in a drainage valve, and then got eaten by American otters.
The British and Irish Association of Zoos and Aquariums has defended the zoo.
A spokesman told the Daily Telegraph: "Staff caring for these animals have been understandably distressed after these sad and unusual events.
"But we are confident that Bristol Zoo is doing everything possible to ensure that similar situations will not arise again in the future."
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