Animal lovers were furious after two antelopes were shot dead after escaping from their enclosure at a wildlife park.
The adult waterbucks were killed after they broke out of Port Lympne near Hythe in Kent and got onto a public footpath.
Waterbucks are a type of antelope found in sub-Saharan Africa.
Carrie Johnson – the Prime Minister wife, a passionate environmental enthusiast – is head of communications at the Aspinall Trust, which helps run Port Lympne’s conservation projects.
A witness said: “My family and I were walking the Hythe loop when we saw keepers with tranquiliser guns; we were stopped and told to go back.
“We heard three gunshots and were told several different stories by different members of staff, then we were told that they had to kill the animals and not to go one way because it would be upsetting to children.”
Port Lympne is a wildlife and safari park which also acts as a breeding sanctuary for rare and endangered animals run by the Howletts Wild Animal Trust charity.
The Aspinall Foundation, where the PM’s wife is communications chief, helps run overseas conservation programmes rewilding animals from Port Lympne and Howletts wildlife parks to protected areas of their natural habitat.
A spokesman for Port Lympne Hotel & Reserve said the decision to euthanise the animals had to be made in the interest of public safety.
They said: “After concerted attempts to get the animals back into their enclosure, it was deemed that, as a category one animal, they could become a danger to the public and the decision to euthanise them was made.
“All of the necessary authorities have been kept fully informed and an internal investigation will take place in due course.”
Animal lovers posting on social media in reaction to the shooting were outraged.
One wrote online: “WTF! Once again due to the inadequacy of humans, more animals are killed at an animal park. We can hardly call their imprisonment conservation when those providing care end up shooting them! “
Another wrote: “Disgusting morons. They could have tranquillised them.”
The pair are Port Lympne’s latest animals to escape from its facility.
Five animals were reported missing in as many months last year.
Two female hog deer escaped on March 5 – one was hurt and the other put down.
A South American jungle cat left its enclosure last May through a hole made by a rat.
A rusty-spotted cat native to India has not returned to its enclosure after disappearing last July.
On August 9, a bear got out of the facility and was coaxed back with food.
It emerged a gate to the pen had been left open by a keeper who was later disciplined.
There have been other animal escapes and keepers have also been killed at the wildlife parked.
Two died in 1984 and 2000 after being crushed by elephants.
The zoo, which has been open to the public since 1976, has insisted it operates with high levels of animal care.