A major incident has been declared by officials in North Yorkshire following "a surge" in coronavirus cases in the past fortnight.
North Yorkshire Local Resilience Forum (NYLRF) said it was reinstating "full emergency mode".
The body, which is made up of representatives from the police and local authorities, said Harrogate and Selby were of particular concern.
Parts of Craven and Scarborough have also seen a sharp rise in cases.
Dr Lincoln Sargeant, the county's director of public health, said there were one to two new cases per day at the end of July.
'Seeing community transmission'
He told a meeting there were now about 20 new cases per day.
"We have escalated our concerns nationally and we are targeting our local testing facilities towards the communities and people in greatest need," he said.
Richard Flinton, chair of NYLRF, said: "In North Yorkshire we have remained at a high level of alert since lockdown eased and we have monitored and managed outbreaks where they have happened very successfully with test-and-trace.
"However, we are seeing community transmission of the virus now and a worrying rise in cases in a number of areas."
"We know how quickly infection rates can change and we are calling on the whole county to act now with us in response." he added.
Concerns about infections in care homes, and testing capacity have also been raised, the Local Democracy Reporting Service said.
NYLRF said it was "stepping up support" for care homes, with some being told to reintroduce visitor restrictions.
Other measures include people being encouraged to wear face masks whenever they leave home, and dedicated police patrols targeting those breaking social distancing rules.
A major incident was first declared at the start of the pandemic, but was subsequently lifted.