Germany has seen the biggest rise in new daily cases of coronavirus since april, a surge that health minister jens spahn described as alarming.

The robert koch institute, germanys main public health authority, said the number of new coronavirus infections had risen by 4,058 in the past 24 hours to a total of 310,144. that was 1,200 more than on wednesday.

Lothar wieler, head of the rki, said it was possible that germany would see more than 10,000 new cases a day, and that the virus will spread in an uncontrolled fashion.

Mr spahn blamed the surge on young people who had become complacent and were no longer properly observing social-distancing rules.

Its above all the younger people who are getting infected at the moment because theyre having parties, because theyre travelling, because they think theyre invulnerable, he said. but theyre not.

The pandemic was, he said, a test of character for us as a society. i want us to pass this test. but we have to do it together.

The new spike in cases is unusual for a country that has so far weathered the pandemic much better than other european countries such as france and spain, with relatively low rates of infection and fewer deaths.

As concern about the proliferation of new cases grows, authorities this week moved to limit domestic tourism to try to avert a second wave. germans from coronavirus hotspots will only be allowed to travel to other regions, such as bavaria, if they can show a negative test result.

Markus sder, the bavarian prime minister, defended the ruling on german tv on thursday, saying some cities were in danger of losing control over the spread of the virus. people must continue to show caution, he said. more masks, less alcohol, and of course smaller parties were the right measures when rates of infection were rising, he added.

In berlin, which has seen a particularly worrying uptick in cases, the local government this week imposed a curfew that will see all bars, cafs and restaurants forced to close between 11pm and 6am a big blow for a city renowned for its thriving party scene.

Mr spahn said the new infections were not originating in shops, hairdressers and public transport, but instead blamed big social gatherings, weddings and religious events.

He said the german health system was still coping with the pandemic. but dr susanne herold, of giessen university hospital, said more and more people were being admitted to german hospitals with covid-19.

She said there were at present 470 patients with covid-19 being treated in german intensive care wards. i fear that will rise significantly in the coming days, she added. we are therefore preparing to admit a new wave of patients who are seriously ill.

Mr spahn stressed that germany had so far got through the crisis well. if you look every day at the map of europe, in terms of high-risk areas you can see that germany has so far been a pillar of strength in this pandemic. he said it was important not to gamble away what weve achieved.