BBC News - FA Cup: Millwall fans arrested after violence: "Police have arrested 10 people after repeated outbreaks of fighting among Millwall fans at Wembley Stadium during the club's 2-0 FA Cup semi-final defeat by Wigan Athletic.
Some supporters were left bloodied while younger fans"
Millwall FC said it could not "allow the actions of a mindless minority" to undermine efforts made to lose the club's reputation for hooliganism.
The Football Association said it deplored the "unacceptable" scenes.
The BBC's chief football writer Phil McNulty said the violence - the first significant trouble at the new Wembley since it opened in 2007 - took place in the closing stages in several areas of Millwall's allocated end.
He said it was a shameful day for Millwall, whose fans made up about 32,000 of the crowd of 62,335, as an increasingly tense atmosphere built up throughout the second half before trouble flared.
Police and stewards moved in to try to stem the violence - witnessed by millions on TV - but it took some time to restore a measure of control.
Millwall chief executive Andy Ambler said in a statement: "Our position is clear - anyone associated with our club found guilty of violent behaviour will be banned indefinitely from Millwall matches in addition to any punishment they receive from the authorities."
Continue reading the main story
Things like that shouldn't be going on -it should be a great day for both sides”
Millwall captain Danny Shittu
He added: "At this stage we are still in the process of establishing the full details of what happened in a section of the ground during the second half.