Blackburn with Darwen is overtaking Leicester as England's coronavirus hotspot, according to official figures.
The Lancashire borough recorded the highest infection rate, with 79.2 cases per 100,000 people in the week up to 17 July, Public Health England said.
Cases have doubled in the past week, with 118 confirmed, compared with 63 in the previous week.
The latest figures are subject to daily revision, but they reflect the position on Sunday night.
New measures to curb the spread of Covid-19 in Blackburn with Darwen have already been introduced after a spike.
New cases in Leicester, where there is a local lockdown, have fallen to a rate of 77.7, with 276 new infections, compared with 429 the previous week.
Analysis
By Daniel Wainwright, BBC England Data Unit
The data on new cases of coronavirus is published every afternoon, and that means new results for previous days are being added in all the time.
So far, looking at the week up to Friday, Blackburn with Darwen has recorded twice the number of cases it had in the previous week, while cases in Leicester - which is in a localised lockdown - appear to be falling.
Last Wednesday, both areas recorded 35 new cases. However, with Leicester having a population more than twice the size of Blackburn with Darwen, that gave the Lancashire borough a higher rate of new cases per 100,000 residents.
Whether Blackburn with Darwen takes the top slot from Leicester should become clearer over the next day or two.
Most new cases in the Blackburn area have been among the south Asian community centred in terraced houses with a high number of occupants, public health officials have said.
Image copyright AFP Image caption Most of Blackburn's new cases are in the south Asian communityProf Dominic Harrison, public health director of Blackburn with Darwen Council, warned that cases would continue to rise.
He said: "We should be concerned the figures have gone up, but I entirely expected them to and I expect them to rise again this week."
Prof Harrison warned a local lockdown could be imposed if things were not turned around.
"We would only use those powers as a very, very last resort," he said.
"We've had good co-operation, so I would be very reluctant to use the powers."
At the weekend it was revealed that contact tracers had reached only about half of Covid-19 contacts in the area.
Image caption Sam Ali urged locals "to realise that the pandemic is still here"Sam Ali, from the Switch Youth Community Organisation in the town, said: "We have all been affected by this.
"Anyone across the country wouldn't like to be on the radar of going into another lockdown, but it's important to realise that the pandemic is still here.
"We need to wear the appropriate masks, we need to wash our hands, we need to keep distant.
"Blackburn is a fantastic town. We're going to get stronger from this."
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