broke onto the Old Trafford pitch, postponing their game against Liverpool on Sunday, as others demonstrated outside the team's hotel.
And it saw some supporters clash with police, with one officer appearing to punch a protester outside the Lowry Hotel where Ole Gunnar Solskjaer's squad were based.
But another Greater Manchester Police officer inside Old Trafford was seen with a “significant slash wound” on his left cheek.
And the authorities have revealed that the policeman, who has been in the service for 20 years, has received life-changing injuries.Stu Berry, chairman of Greater Manchester Police Federation, said: "Our brave colleague went to work yesterday to keep the people of Greater Manchester safe - and he ended up coming under.
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