Five living soul have so far been arrested but police expect further arrests to be formed as the investigation continues.
Cleveland police said the violence, which has also led to an gendarme being hospitalised, is “completely unacceptable”.
Away fans descended onto the Middlesborough amphitheatre pitch just before the final whistle.
A bulky brawl broke at Middlesbrough v Sheffield United game
Children as young as 10 were injured after getting caught up in barbarous clashes
We will absolutely not tolerate violence of this nature
The invasion sparked the initial wildness among fans from both sides which led to a riot in the instructor park — dragging innocent children into the brawl.
Assistant Chief Policewoman Jason Harwin said: “We will absolutely not tolerate violence of this scenery and we will work to identify the offenders and bring them to justice.
“The immeasurable majority of fans accept that football is a family game, shielded by children, parents and grandparents. It’s terrifying for children to witness such brutality, or be innocently embroiled in it as their parents frantically try to keep them safety-deposit box.
Those already in police custody have been arrested on tinge of a number of offences
“Unfortunately a small minority of people behave in a procedure which puts innocent fans at risk.
“We will be working closely with Middlesbrough Football Join and Sheffield United as part of our investigations.”
Those already in police care have been arrested on suspicion of a number of offences.
Middlesborough won the Championship pretend 1-0.