Liverpool Football Club has sent a letter to all supporters who attended their Carabao Cup game at Manchester City in December to try to find the fan who seriously injured a teenage girl.
The letter is calling for anyone who has evidence to help Greater Manchester Police's (GMP) investigation.
The Reds lost 3-2 at the game at the Etihad, but the tie was marred by a number of reported incidents off the pitch - including a projectile thrown from the away end which cut open the head of a 15-year-old City fan below.
The girl's father posted on social media, detailing how a 'weighted pint pot' landed on his daughter's head, forcing her to need glue to stop the bleeding.
Shortly after Christmas Day, he added, Liverpool Chief Executive Billy Hogan rang the family to personally apologise.
In his post on social media the dad said: "The pot ‘smashed’ on impact, she suffered a head injury and was ‘glued’ at the ground before being released later that evening.
"The incident occurred about 20 mins in, just after Liverpool’s first equaliser."
He continued: "We have had a call from LFC directly, Billy Hogan, who apologised unreservedly on behalf of the club and I would like to stress they are as committed as we are to rooting this individual out of football and for them to face the consequences of their actions.
"I would like to thank the dozens of Liverpool Football Club fans who have contacted us so far with kind messages of support in finding the perpetrator and also all friends and contacts who have been in touch."
Both clubs have pledged to look into the various disturbances while GMP is also investigating following a number of additional incidents.
In a letter to their fans, Liverpool said: "Ahead of our fixture at Manchester City on 22nd December, both club chief executives wrote a joint letter to all match going fans to ask for full support in tackling behaviours and actions that have no place in our game.
"In this letter we also explained our commitment to dealing with any unacceptable behaviours and our intention to take action by issuing sanctions to those found to be responsible for any issues and incidents.
"This resulted in a 15 year old girl sustaining a serious head injury, an incident which is now being investigated by Greater Manchester Police.
"It has also severely knocked her confidence to attend football matches in the future.
"If you have any evidence that could support the police investigation, we strongly urge you to report this."
GMP said: "It is believed the cup was thrown inside the Etihad Stadium at around 8.25 pm from the upper tier down to the lower tier in the stadium, which subsequently hit and injured a 15-year-old girl causing a 1-inch laceration to her head.
"The girl was taken to hospital where she received medical attention. GMP are appealing to the public for further information to help us locate the person/people responsible for this malicious attack."
The vast majority of Liverpool fans have been supportive of the girl and her family in the wake of the shocking incident, with several providing messages of support on social media.
Recent meetings with City have been tainted with fan disorder from both sides, with the two clubs coming together ahead of the Carabao Cup clash to call for a calming of rising tensions.
After the game, both City and Liverpool released another statement, thanking 'the vast majority of fans for their behaviour' before adding that a full investigation was underway regarding the 'hugely disappointing incidents'.
They added: "Manchester City FC and Liverpool FC are fully committed to working together to eradicate these issues from our fixtures. They have no place in football.”
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