Monaghan residents claim that a significant increase in local deaths from cancer may be linked to the number of aerials for mobile phone and radio communications networks that are attached to an ESB mast.
The residents, from the Killygoan part of the town, say 23 people have died from cancer in the area surrounding the mast, which is adjacent to several dwellings. A number of other people are also undergoing treatment for varying forms of cancer.
The residents are protesting against the ESB's decision to allow the mast to be used by the networks.
Monaghan town councillor Mr Donal Sherry said the incidence of cancer had risen rapidly in the immediate area since the additional aerials were affixed.
In a statement, the ESB rejected claims that the mast posed a radiation hazard. It said radiation levels, which were monitored, were lower than in many other towns.
It said that when the mast was erected some 40 years ago, there were fewer dwellings in the immediate area. The ESB had discussions over the years with local authorities in the area and it was accepted that the mast posed no threat to health, it said.
The mast was required for the provision of an essential communications service for the community, the statement added.