The number of lab-confirmed cases of coronavirus in the UK has surpassed half a million after 22,961 positive tests were reported in the 24 hours up to 9am on Sunday.
Based on the latest government data, the total number of Covid-19 cases in the UK now stands at 502,978.
A computing error has been blamed for the surge in daily cases across the weekend, with a message on the government's coronavirus dashboard warning Sunday's figures are "artificially high for England and the UK".
A total of 15,841 cases were recorded between September 25 and October 2 but not included on previous daily updates because of a technical issue.
The majority of these cases occurred in most recent days, PHE said.
Prime Minister Boris Johnson has admitted: "There was a failure in the counting system which has now been rectified."
The government also said a further 33 people had died within 28 days of testing positive for Covid-19 as of Sunday - the latest fatalities bring the UK death toll to 42,350.
Separate figures, published by the UK’s statistics agencies, show there have been nearly 57,900 deaths registered in the UK where Covid-19 was mentioned on the death certificate.
How were nearly 16,000 cases missed off the daily updates?
A "failure in the counting system" - now fixed - has been blamed for the dramatic rise in cases across Saturday and Sunday.
Public Health England (PHE) said its investigation into the issue with the government’s coronavirus dashboard identified 15,841 cases which were not included in daily reports between September 25 and October 2.
For example, 4,786 cases which were due to be reported on October 2 were not included in the daily total on the dashboard that day - when the figure was given as 6,968.
The issue was identified overnight on Friday 2 October.
Michael Brodie, the interim chief executive at Public Health England, said: "Every one of these cases received their Covid-19 test result as normal and all those who tested positive were advised to self-isolate.
"NHS Test and Trace and PHE have worked to quickly resolve the issue and transferred all outstanding cases immediately into the NHS Test and Trace contact tracing system".
Mr Brodie said "further robust measures have been put in place" to stop it happening again.
Test and Trace and PHE joint medical adviser, Susan Hopkins, said the issue had not prevented people receiving their test result and had not affected decision-making in local areas with regard to restrictions.
Here's how many cases were missed on each day:
957 cases on September 25, when the original figure given was 6,874
744 on September 26, when the original figure given was 6,042
757 on September 27, when the original figure given was 5,693
none on September 28, when the original figure given was 4,044
1,415 on September 29, when the original figure given was 7,143
3,049 on September 30, when the original figure given was 7,108
4,133 on October 1, when the original figure given was 6,914
4,786 on October 2, when the original figure given was 6,968
The death toll among people who tested positive for coronavirus and who died in hospital in England has risen by 28.
According to NHS England the total number of confirmed deaths reported in hospitals now stands at 30,166.
Wales reported no further deaths in the past 24 hours, but 430 new Covid cases were confirmed, with much of the country still in some form of localised lockdown.
Cases jumped in Scotland too, with 758 new confirmed coronavirus cases reported on Sunday. No new deaths were recorded.
The Covid-19 death toll in Northern Ireland is at 584. The country recorded 462 new cases in the past 24-hour period.