DETECTIVES are closing in on the thug who left a man fighting for his life in hospital following a mass brawl after the weekend's Old Firm match.

The victim, named locally as Francis McCann was stabbed during the massive rammy on Blackfriars Street around 5pm on Sunday, just hours after Celtic defeated bitter rivals Rangers.

He was rushed to the Glasgow Royal Infirmary along with two other men, aged 29 and 30-years-old respectively, who have since been released.

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Police confirmed they are following a positive line of enquiry as they hunt for those responsible. 

Detective Inspector Peter Crombie, Major Investigations Team, said: "The 47 year-old sustained very serious injuries in this attack, and is still in a critical condition. His family are distraught.

"We are doing everything we can and are particularly looking for mobile phone footage of the incident as it could be the crucial piece in this investigation.

"You may think that someone else will have got in contact so you don't have to, this is not the case and we need to speak to everyone who was there that evening and witnessed this incident.

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"We want to thank those who have come forward in the past few days and would continue to encourage those who have not to get in touch with us via 101, quoting incident number 2923."