Police and vets are investigating after three horses were found dead in a field.
The horses from Blue Acre Horse Rescue on Ham Island, Old Windsor, were found on 23 August by the centre’s co-founder Bob Regan.
“When I arrived on Monday morning one was lying on the track dead and two others were lying dead nearby,” he told H&H.
“It was a bit of a shock.
“There is nothing wrong with the others.”
The rescue centre, which was founded in 2002, currently has 35 horses on site at its 40-acre farm.
Mr Regan added he called the vets – Chiltern Equine – who came and collected the bodies and took them for testing.
Mr Regan said that an initial autopsy proved inconclusive and samples have been sent off for further analysis.
“We can’t work out what it was – there weren’t any signs,” he added.
Two of the horses, Nelson (pictured, above) and Spirit – both aged between eight and 10 years old –belonged to his Mr Regan’s stepdaughter Rebecca, who he said is “heartbroken”.
The other, a pony called Freddie, belonged to the other co-founder of the rescue centre Caron North.
“He was a great little pony with kids,” she said.
“Three horses don’t just drop dead overnight.”
Thames Valley Police have said that poisoning is suspected.
“They had no obvious injuries and were fine the day before, but had blood around their eyes and rectums,” said a spokesman.
“They appear to have just dropped in a cluster, where they stood.
“Other horses in the field have eaten the same food and drunk from the same water containers, but appear unaffected.”
A police spokeswoman told H&H on Thursday (27 August) that the investigation is ongoing.