Trouble had reportedly flared after a bar being frequented by English fans was targeted by a group of locals in a city that has been on high alert over political and social unrest over recent days. There are demonstrations scheduled for Wednesday in Taksim Square as protests escalate against the current government in Turkey.
That in itself is a concern as Chelsea fans have been instructed to meet in the square before being bussed to the stadium on Wednesday evening. The British Consulate have been contacted by Chelsea officials in Turkey, with the Foreign Office confirming they were "looking into reports" and would be providing consular assistance if required.
Chelsea had offered advice to travelling supporters on their website earlier this week. "While Istanbul is generally a safe city and the police have not given any specific areas to be avoided (other than the Metro to the stadium on match day), supporters should be aware of pickpockets, petty theft and bag snatchers in crowded places," it read. "Care should be taken to keep bags and cameras secure and not to keep on show any other valuables. Supporters are advised to leave their passports in the hotel safe and use another form of photographic ID."
Chelsea anticipate around 1,300 of their fans to attend the fixture at the Turk Telekom Arena on Wednesday evening, with the majority travelling out on the day of the game.