Scientists and health officials say that revellers meeting for “lockdown parties” and “end of world” drinking sessions were acting irresponsibly by contributing to the spread of the virus.
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The police also report that “corona speakeasies” have been springing up in the city, where owners of closed bars have taped up the windows and locked the doors, only allowing in guests who have registered, or who deliver a specific knock on the door.

In a tweet, Berlin police warned: “If you run a bar, tape up the windows and allow people to enter only by knocking or arranging to come in advance, then you should know that we’re not living in a situation like Chicago of the 1920s, instead it will trigger a police operation.”

[ https://www.theguardian.com/world/2020/mar/18/fears-lockdown-parties-will-increase-global-spread-of-coronavirus ]