Fed-up villagers in Bicton, near Shrewsbury, are demanding answers over where the flies are coming from and why they have lingered for more than a month.

But health officials say they have thoroughly investigated the problem and cannot find the source.

Stuart and Linda Leighton, who live in the village, said the flies had been so bad they had caused their cat to become ill.

Mr Leighton said: “We are still having a problem and I have been on to the council but they don’t seem to know.

“We have got a cat and we can’t leave food down for her because she has been violently sick from the flies.

“And they are around in the house when you are trying to eat food. It’s been going on since the beginning of September,” he added.

“When it is warm and the sun is shining we get swarms outside at about 6pm.”

Dave Spode, environmental health manager for Shrewsbury & Atcham Borough Council, said: “It’s still something of a mystery. We have put a lot of time into investigating complaints from residents in Bicton.”

He added: “Last year we had a problem with a poultry house and we served a legal notice and that was one of the first places we looked at. But that particular premises is being managed properly and was not the source.

“We are still in a position of asking residents that if they think of a specific source, please let us know.”

The flies have been identified as the “lesser house fly” and are often, but not exclusively, associated with poultry houses. There have been increased fly infestations nationally this summer.

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