Park officers are being vigilant after reports of dogs falling ill after eating drug users’ poo last week.
Two dogs became unwell after being walked in Views Wood and West Park Nature Reserve in Uckfield last Tuesday and Wednesday.
One incident was reported to police, who are now working with the district and town council.
The force says it’s ready to take action if there’s any evidence of a wider health issue or a crime being committed.
A spokeswoman for Wealden District Council said: “We are aware of these reports and monitoring the situation for any similar instances.
“We are in contact with Uckfield Town Council, and our officers in the area remain vigilant for any signs of such antisocial behaviour.
“In the meantime should dog owners believe their pet has fallen ill following a walk they should contact their vet for advice.”
A police spokesman said: “Police received a report of a dog having become unwell after being walked in Views Wood, Uckfield.
“Our neighbourhood policing team are aware and engaging with local partners.
“Appropriate action will be taken should there be any evidence of a wider health issue or criminal element.”