There was a series of brawls in some of the outdoor pools this summer, which together with the eternal fear of immigrants caused a media frenzy. (Berlin's pools where suddenly national news)
This is probably the reaction to those events.
https://en.wikipedia.org/wiki/Lebanese_Civil_War https://en.wikipedia.org/wiki/Yugoslav_Wars https://en.wikipedia.org/wiki/Syrian_civil_war
I do see increased police presence during events like Karneval, but that's not unreasonable with tens of thousands of people drinking and partying on the streets.