At least 41 schools in Berlin have reported that students or teachers are infected with coronavirus - less than two weeks after they reopened in the German capital.
The Berliner Zeitung published the numbers and the city's senate for education confirmed them.
Hundreds of students and teachers are in quarantine, the newspaper reported. Primary schools, high schools and trade schools are all affected. There are 825 schools in Berlin.
The reopening of schools and the risk of virus clusters building up there and spreading to families and further into communities has become a matter of great concern.
Berlin was one of the first places in Germany to reopen schools after the summer holidays.
Children are obliged to wear masks in hallways, during breaks and when entering the classroom, but they can take them off once they sit down.
Some critics say the measures are too relaxed and both students and teachers should wear masks.
German Chancellor Angela Merkel said there are too many different regulations in place across the country and "people simply don't understand" why they are allowed to do one thing in Berlin that may be banned in Bavaria.
Yesterday, Germany's disease control centre registered 1,426 new cases.
Meanwhile, Spain diagnosed 3,650 coronavirus infections in the past 24 hours, the health department said yesterday, up from 3,349 cases reported a day earlier and bringing the cumulative total to 386,054.
Officials said 125 people had died from the virus over the past seven days. The seven-day death toll reported on Thursday was 122.
Deaths from the virus have risen since Spain lifted a three-month lockdown in late June, but they remain far below the levels seen during the epidemic's late-March peak when the daily toll approached 1,000.
One region has ordered all brothels to close after recent coronavirus clusters highlighted the difficulties of tracking contagion in these premises. The Castilla La Mancha region, which has the country's highest number of brothels, ordered them to close by tomorrow.
That came after a dozen positive Covid tests were found among seven women and five men at a brothel in the central Ciudad Real province.
Slovakia reported 123 new cases, its highest daily number since the global pandemic reached the country in March.
It was also the third time the country has reported more than 100 new cases in a day.
Slovakia, a country of 5.5 million, has recorded very low numbers of the coronavirus compared with the rest of Europe. It has confirmed 3,225 people infected so far, out of whom 2,045 have recovered, and 33 deaths.
South Korea has added its most new coronavirus cases in months, driven by a surge around the capital that appears to be spreading nationwide. The 324 new infections were the country's highest single-day total since early March and the eighth consecutive triple-digit daily increase.
Poland reported 903 new cases, the highest daily rise since the pandemic began.
The Philippines recorded 4,786 new coronavirus infections, taking its total confirmed cases to 182,365 since the pandemic began, the highest in Southeast Asia.
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