Croatian unmarked police. Plus, I can confirm, from my own personal experience, they also drive a black Audi A4. Me being in the same car didn't help my case. : r/Audi
Police cars outside police station Trg Josipa Jurja Strossmayera square Donji Grad district central Zagreb Croatia Europe Stock Photo - Alamy
RARE* Belgic police cars in Zagreb, Croatia - YouTube
Skoda Octavia Croatian Police car Policija Samobor Croatia… | Flickr