https://www.flightradar24.com/data/flig ... 46#dafc6b4
News story (in German) http://www.bild.de/regional/koeln/easyj ... l#fromWall
An easyJet A319 operating flight U23246 from LJU-STN made an immediate diversion to CGN this evening due to a bomb threat. A passenger reported overhearing a threat to the crew, the aircraft was diverted immediately to CGN. An unaccompanied piece of baggage was destroyed as a precautionary measure, and several people were arrested.

Looks like they used the slides to evacuate.