Dortmund play PAOK for the Europa League group stage and published an announcement about the game in Thesaloniki.
The announcement mentioned: "They see us as rivlas because we have the same colours with Aris so it will probably be a dangerus game for us. It's better to wear neutral colours. Don't stay near Toumpa but near the "Lefkos Pyrgos" since there the policing is better. Don't yell team song before the match at the center of the city. We will meet at 20:30 at the "Lefkos Pyrgos". The ID will be checked and you should not wear any team scarves. Do not hold flags. After the game there will be curfew".