The Department for Agriculture, Environment and Rural Affairs (DAERA) said it is "very concerned" by the dumping of animal carcasses in Northern Ireland.
The comments follow several cases in recent months of dead animals being dumped at locations in counties Tyrone and Derry.
In recent days, dead sheep and calves were found dumped at two locations in Co. Tyrone.
Up to 15 dead sheep were dumped in the Ballygawley Water which is a tributary of the Blackwater River, which feeds into Lough Neagh, a major drinking water source in Northern Ireland.
Two dead calves were later found dumped on a roadside near the village of Cappagh.
In April, a dozen of dead lambs were illegally dumped in Derry, while animal carcasses were also discovered on a road in Tyrone.
The incidents have been condemned by local representatives.
A DAERA spokesperson told Agriland that the department is "very concerned about these latest incidents and is investigating them".
"Animal by-products are a potential source of risk to public and animal health.
"Farmers have a legal obligation to dispose of animals in a safe and sustainable manner instead of leaving it for other landowners, local councils or DAERA to recover and dispose of the remains.
"This is a highly irresponsible and illegal act, therefore, it is vital that members of the public with information about who is doing this come forward with information to ensure those responsible face justice," the spokesperson added.