A coronavirus outbreak at a caravan park has seen 21 people test positive for the bug.
The site in the town of Craven Arms in Shropshire has been besieged by the virus after two cases were confirmed last week.
A testing site was set up at a nearby business centre, which has carried out tests on 41 people from the residential park.
It discovered that 21 of them had the coronavirus.
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 with those who tested positive to quarantine for at least seven days.
Contact tracing is being undertaken in a bid to control the outbreak, Shropshire Council has said.
The authority is delivering essential goods including food and prescriptions to the caravan park.
A playground close to the caravan park has also been closed to help reduce social contact and the risk of transmission.
In a statement the council said: "As of today, 21 positive cases on the site have been confirmed.
"Offers of testing to all residents at the site continue, as we expect to see the number of positive cases rise in the coming days, before infection control measures and social distancing start to take effect.
"All residents on the caravan site have been asked to self-isolate with members of their households for 14 days following contact with a positive case.
"Those residents who had tested positive for coronavirus were asked to self-isolate for a minimum seven days from the time they started showing symptoms or from when they took their test.
"If those who have been in self-isolation for the minimum seven days are now well enough, they can finish self-isolation and leave their home.
"This means that initial positive cases will finish isolation this coming week."
A testing centre has now been set up on a nearby business park, and everyone living on the site has been offered a test
The centre will be open for the next two weeks between 10.30am and 3.30pm and those living nearby can book a test online via NHS Test and Trace or by ringing 119.
Councillor David Evans urged people at the park to play their part in stemming the outbreak.
He 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."
He 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."
