Uefa has ordered German Bundesliga football team Cologne to pay a fine of €60,000 (£53,000/$69,800) to Arsenal for damages caused following the Europa League match at the Emirates in September.
An estimated 20,000 Cologne fans were in London prior to the match, despite the club having an allocation of just 2,900 tickets.
Thousands of ticketless supporters descended on the stadium in the lead-up to the match and there were a number of scuffles between fans and stewards once the gates to the venue were opened.
Thousands of Cologne fans reportedly accessed the home sections at the Emirates Stadium, causing a security risk.
European football’s governing body also decided to issue a one-match travel ban for supporters, under a two-year probationary period.
Cologne was handed four charges, including one of crowd disturbances and also acts of damage, setting off fireworks and throwing of objects.
Uefa has ordered the German club to contact the Premier League club within 30 days for the settlement of the damages caused by its supporters.
Initially, Arsenal had been charged under Article 38 of the Uefa Safety and Security Regulations, over stairways being blocked in the away supporters section. Uefa have elected not to open disciplinary proceedings.
Previously, Cologne fans told the Guardian newspaper that they were able to purchase tickets in the home end through Craigslist, independent ticket touts and websites such as Viagogo and Ticketbis, owned by StubHub.
One Cologne fan said he got his tickets on Craigslist from a seller who had several seats to list, according to the Guardian. “I got a phone number and messaged with that guy via WhatsApp,” he said. “It was £100 for a seat near the away block of the Cologne supporters.
“He sent me my ticket as a PDF via email and I paid him via PayPal. I also gave out his number to a couple of fans who were looking for tickets as well so I guess he had plenty to sell.”