Environmental health officers are trying to find the source of a fly invasion after numerous complaints about the insects invading homes.
People in the Shrewsbury area have complained about the increased number of flies in their houses.
The insects have been identified as the lesser house fly but the source has not yet been found.
A spokesman said the problem reflected increased fly infestations reported up and down the country.
The lesser house fly can be associated with poultry houses.
The problem seems to have centred on the Bicton and Yockleton areas.