The suspect within the assault on the Christmas market in Magdeburg threatened an assault in Mecklenburg-Western Pomerania years in the past. No actual hazard was seen there. Later he even known as the Chancellery.
https://www.spiegel.de/panorama/justiz/taleb-al-abdulmohsen-drohte-aerztekammer-2013-mit-anschlag-a-0fd8a57f-2b9f-4d34-b923-dc424306ac2e#ref=rss