Arsenal fans' group condemns "yobbish" Cologne trouble makers at Europa League tie
The Group H opener was delayed by an hour as many away supporters without tickets looked to gain entry to the ground, with Arsenal eventually running out 3-1 winners.
The visitors were issued with 3,000 tickets but around 20,000 Cologne fans are believed to have made the journey to London.
UEFA has opened disciplinary proceedings against both clubs. Cologne face charges involving crowd disturbances, setting off fireworks, throwing of objects and acts of damage by their fans, while Arsenal are under investigation for having "stairways blocked" in the away supporter section.
There were clearly thousands of away supporters sat among Arsenal fans, causing a security risk.
Five arrests were made over the course of the evening and Arsenal issued a statement on Friday insisting the safety of supporters was the main concern at the time. Arsenal promised a "full review" would be undertaken to discover how the events were able to occur.
Lois Langton, chair of AISA, said in a statement released to Press Association Sport that the "yobbish abandon" of some Cologne supporters must not go unpunished.
"The behaviour of a number of Cologne supporters yesterday was a dangerous throwback to a bygone era," she said.
"It is only right that charges have been swiftly brought and UEFA must sanction Cologne in the way that it doubtless would had an English club's supporters behaved in such a disgraceful manner.
"Whilst Arsenal also face charges with serious questions needing to be answered, including how so many Cologne supporters were able to infiltrate the home end, the fact of the matter is that it was the Cologne supporters who behaved with yobbish abandon; there can be no excuses made for those supporters who caused trouble."
Langton also praised home fans for avoiding confrontations with those Cologne fans seated in home sections - particularly as they celebrated Jhon Cordoba's opening strike.
"It's to the credit of Arsenal supporters not to have become engaged," she added.
Former Germany international Lukas Podolski came through the ranks at Cologne before spending three years at the Emirates Stadium with Arsenal.
He took to Twitter to defend the behaviour of the vast majority of travelling supporters.
"Because of 50 people everything is made bad. Laughable! The mood in the stadium was great," he wrote.
"Nobody's talking about that, and the #effzeh (Cologne) also played well! Cologne shouldn't need to hide or be ashamed that was a really great atmosphere more than the Champions League !!!"
When it was put to him by a German television presenter that 50 trouble-makers was 50 too many, Podolski replied: "50 out of 20,000? Every Oktoberfest or other event is worse. Where is the outcry then?"
The presenter, Florian Konig, then re-stated that the problem was the 50 causing trouble and not the reporting of it.
Podolski said: "Then please read the reports. Always looking for the needle in the haystack. Highlight the performance and the fantastic atmosphere in the foreground."