The 15-year-old girl was hurt at the game and police are looking into it.
The girl was taken to the hospital.
The police are looking into an assault on the junction of Alan Turing Way and New Road.
A man was arrested for a racially-aggravated public order offense.
Two more men were arrested on suspicion of trying to explode a firework.
The tie was won by Manchester City.
Coins and a smoke bomb were thrown during the match.
From the night, we will be investigating the incidents.
Throwing objects in a confined area can be dangerous.
The incidents were "wholly unacceptable" according to the statement.
The people who are found to be responsible for the incidents will be subject to the sanction process of their club.
Both Manchester City andLiverpool are committed to eliminating these issues from our games. They can't play football.
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