Police were calling on any information which might lead to the discovery of the offenders behind the plot.
"This is a popular area where children often play and people regularly walk their dogs, it's really disappointing to see these people put at risk," he said.
"Police are extremely concerned by this offending and would like to find the people responsible.
"We ask that anyone who may have witnessed anything suspicious in this area recently or has any other information valuable to our investigation comes forward and contact police."