Officials in Shropshire fear they may be witnessing the early stages of a new outbreak of the coronavirus after 21 people tested positive in one town.
Two positive cases of the virus had already been identified in a caravan park in Craven Arms last week.
Those cases had in turn had been linked to another outbreak at a caravan park in Welshpool.
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Now about half of those tested for the virus in Craven Arms have returned positive results – with the BBC reporting 40 people have been checked so far.
A testing centre has been set up in a nearby business park, and everyone living on the caravan site has been offered a test. Meanwhile all residents who have come into contact with one of the positive cases have been asked to self-isolate with their households for 14 days.
A playground close to the caravan park has also been closed to help reduce social contact and the risk of transmission.
Councillor David Evans said: “Our priority is to protect the health and wellbeing of our local residents.
“I’ve been in Craven Arms to talk to residents and businesses to answer any questions and reassure them that the risk to the general public is low.”
Shropshire County Council said staff had visited the site to provide residents with information on how to prevent the spread of the virus, as well as information on its symptoms and what to do if they are feeling unwell.
The authority added it had been distributing personal protective equipment, hand sanitiser, cleaning products along with other supplies to residents.
Mr Evans added: “I would like to thank members of the community for their own ongoing support and cooperation.
“We continue to rely on everyone at the site playing their part, and want to encourage the residents to continue to self-isolate and take all the necessary precautions.
“This is the only way we can help stop the spread of the virus.”
Additional reporting by Press Association