FAN behaviour at Sunday's Old Firm clash was the "worst in 15 to 20 years", a police leader has said.
David Hamilton, vice-chairman of the Scottish Police Federation, said match authorities are battling "an escalation in violence".
Read more: Man, 47, critically ill after mass brawl after Old Firm derby
It comes as the 47-year-old fighting for his life after a mass street brawl in Glasgow between rival fans was named as Francis McCann, from Drumpchapel.
The Celtic fan, who was stabbed in the neck during the fight in the Merchant City area, remains critically ill in hospital.
Police are treating the attack as attempted murder and investigations are ongoing.
Read more: Neil Lennon - 'I will rebuild Celtic around Scott Brown'
Two other men, aged 29 and 30, were also stabbed in what Police Scotland have described as serious assaults.
The incident, which broke out shortly after 5pm on Sunday March 31, came just hours after a bad-tempered 2-1 showdown between Celtic and Rangers at Parkhead stadium.
Mr Hamilton said the behaviour of players had been unacceptable during the match, exacerbating tensions between fans.
Rangers pair Alfredo Morelos and Andy Halliday were shown red cards for clashes with Celtic captain Scott Brown.
Read more: Children screamed as street brawl turned Mother's Day in Merchant City into 'bloodbath'
Brown had celebrated in front of Rangers fans at full-time led to a bust-up with Halliday which sparked a mass fracas.
Some Celtic fans spilled on to the pitch after their side's opener and flares were also thrown during the match.
Mr Hamilton told BBC's Sportsound: "It's despairing the way some fans are behaving in Scottish football," Hamilton said. "We're seeing an escalation in violence both in terms of severity and frequency.
"At the weekend, some of the officers who were working at Celtic Park were saying it's the worst they've seen in 15-20 years of service.
"An officer had a flash-bang thrown at him that just missed his head."
It comes amid warnings from Justice Minister Humza Yousaf that he will not rule out legislating for strict liability, which would see clubs held responsible for fans behaviour at grounds.
Campaigners believe it would help tackle sectarianism and hooliganism.
Why are you making commenting on The Herald only available to subscribers?
It should have been a safe space for informed debate, somewhere for readers to discuss issues around the biggest stories of the day, but all too often the below the line comments on most websites have become bogged down by off-topic discussions and abuse.
heraldscotland.com is tackling this problem by allowing only subscribers to comment.
We are doing this to improve the experience for our loyal readers and we believe it will reduce the ability of trolls and troublemakers, who occasionally find their way onto our site, to abuse our journalists and readers. We also hope it will help the comments section fulfil its promise as a part of Scotland's conversation with itself.
We are lucky at The Herald. We are read by an informed, educated readership who can add their knowledge and insights to our stories.
That is invaluable.
We are making the subscriber-only change to support our valued readers, who tell us they don't want the site cluttered up with irrelevant comments, untruths and abuse.
In the past, the journalist’s job was to collect and distribute information to the audience. Technology means that readers can shape a discussion. We look forward to hearing from you on heraldscotland.com
Comments & Moderation
Readers’ comments: You are personally liable for the content of any comments you upload to this website, so please act responsibly. We do not pre-moderate or monitor readers’ comments appearing on our websites, but we do post-moderate in response to complaints we receive or otherwise when a potential problem comes to our attention. You can make a complaint by using the ‘report this post’ link . We may then apply our discretion under the user terms to amend or delete comments.
Post moderation is undertaken full-time 9am-6pm on weekdays, and on a part-time basis outwith those hours.
Read the rules hereLast Updated:
Report this comment Cancel