Laundered diesel pods have been found dumped on a rural roadside close to the Monaghan-south Armagh border.
The incident occurred on the Upper Darkley Road in Keady.
Sinn Fein Councillor Bróna Haughey said this "ongoing criminal activity cannot continue", adding that they have "no regard for the environment".
Fellow Sinn Fein Councillor Barra O'Muiri labelled those responsible as "scumbags" who should be ashamed of themselves and their total disregard for the environment in which they live.
This incident comes less than a week after dozens of tyres were dumped on the Loughaveely Road in south Armagh, less than ten kilometres from the County Monaghan border.