Manchester United will punish fans who committed criminal acts during the protests on Sunday which led to the Premier League game against Liverpool being postponed, the club said on Monday.
United fans protesting against the club's American owners, the Glazer family, stormed into the stadium which was closed to fans due to COVID-19 restrictions.
"The majority of our fans have and will condemn criminal damage, along with any violence towards club staff, police or other fans, and these now become a police matter," United said in a statement.
"The club has no desire to see peaceful protestors punished, but will work with the police to identify those involved in criminal activity, and will also issue its own sanctions to any season ticket holder or member identified, per the published sanctions policy," the statement added.
A flare was thrown at the broadcasters podium as fans ran on to the field and protesters clashed with police outside the ground.
Greater Manchester Police (GMP) said six officers were injured during the demonstrations, with one suffering a fractured eye socket, and another sustained a wound to his face, following bottles and cans being thrown from the crowd.
A third officer was dragged and kicked.
GMP said a 28-year-old man has been arrested in connection with the protests and added that it was "reviewing all obtainable evidence" to identify the organisers of the demonstration and those responsible for assaulting officers.
"The behaviour shown at this protest was absolutely atrocious," GMP Assistant Chief Constable Nick Bailey said in a statement.
"Officers were just trying to do their job and facilitate a peaceful protest."
