German authorities worked through the night to clear a backlog of coronavirus tests from travelers after it emerged 900 people who were positive for COVID-19 had yet to be informed.

Bavarian Health Minister Melanie Huml said all people with positive results would be informed Thursday and that systems were being improved to prevent any further delays.

Bavaria has been offering free voluntary tests at airports, as well as specific train stations and highway rest areas, and has carried out some 85,000 since the end of July, Huml said.

The interest was higher than expected, and the delays were almost exclusively at the rest areas and train stations, where some 60,000 people were tested. Those operations were initially run by aid organizations, but are now being taken over by private companies, which are digitizing the transmission of the results, among other things, the dpa news agency reported.

Federal Health Minister Jens Spahn told ZDF that the delay in communicating the results of 44,000 tests was “annoying, without a doubt” but that Bavaria was heading in the right direction.

“Basically I'm very grateful that we are testing so extensively and that Bavaria also makes it possible to take tests at rest stops when entering the country by car,” he said. “But then, of course, the results have to be transmitted.”

It was not yet clear which countries the people who tested positive were from, nor where they were staying, dpa reported.

As of Saturday, any travelers arriving from high-risk areas have been required nationwide to take coronavirus tests.