Authorities have said seven people appear to have been infected with the coronavirus at a restaurant in northwestern Germany.
It would be the first known such case since restaurants started reopening in the country two weeks ago.
The local government in Leer county said on Friday night, that the cases reported between Tuesday and Friday led to at least 50 people being quarantined.
Previously, no new cases had been confirmed in the area for over a week.
Authorities didn't detail how and when the infections are believed to have happened.
Germany started loosening its coronavirus restrictions on April 20 and that process has gathered pace recently.
Lower Saxony state, where Leer is located, allowed restaurants to reopen May 11 with hygiene precautions.
They include a two metre distance between tables, masks for waiters and an obligation to take the name, address and phone number of guests so that possible infections can be traced.