Dog owners have been warned to "exercise caution" after rat poison was found scattered in a popular walking spot in Soham.
East Cambridgeshire District Council said it had been made aware of a "large amount" of rodenticide in a grass meadow to the rear of Dobede Way in Soham.
It did not confirm whether the act was pre-meditated, but said landowner Taylor Wimpey had been informed.
The developer said it was "aware" of the situation and is currently carrying out checks to ensure contamination is addressed.
A spokesperson for Taylor Wimpey told the Ely Standard: “We are aware of the incident and understand the concern this will have caused to residents and members of the public who access the land.
“We would like to assure the community that, as a responsible landowner, we are taking action to remove the substance as soon as possible.
"We are working with specialist consultants who are on site to begin this process and to carry out further checks to ensure any areas of contamination are addressed.
They added: “Until this process is completed, we ask residents to exercise caution when passing through this area and thank them for their cooperation.”
The area will remain closed until it has been declared safe by specialist consultants.
All cost associated with the work to remove the substance will be covered by Taylor Wimpey, the developer confirmed.
Taking to social media, residents have expressed outrage and concern over the potential harm to local wildlife.
One resident said: "Thinking of the poor wildlife this may have hurt and hoping no children or pets are in harms way.
"This is such a vile thing for someone to do. A very cruel and nasty act."
Rat poison is extremely toxic for dogs and other pets, and symptoms can include internal bleeding, brain swelling, hypercalcemia, organ damage and is some cases, death.
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