An investigation has been launched into the cause of fly infestations in Cwmcarn.
Residents have complained that swarms of the pest have been invading their homes at night.
This prompted Natural Resources Wales to launch an investigation to find the cause of the problem.
However, after inspecting a nearby recycling site, Natural Resources Wales and Caerphilly County Borough Council have yet to find the cause of the infestations.
Caroline Drayton, from Natural Resources Wales, said: “The officers were able to verify that the flies are not originating from the site run by GLJ Recycling Ltd.
“Caerphilly County Borough Council is investigating other potential sources.”