WIDNES rugby league fans stormed onto a the field at Leigh Sports Village before ripping off the Castleford mascot's head and kicking it around the pitch.
A number of Widnes Vikings supporters invaded the pitch immediately after they were beaten 28-6 by Castleford Tigers in the Challenge Cup semi-final yesterday.
Violence broke out as police and stewards attempted to restore order, and many pictures of the trouble have emerged via social media, including one of the head being removed from one of Castleford's tiger mascots and kicked away.
Now an appeal for information has received an "overwhelming" response, Widnes bosses say.
A statement released by the RFL and Leigh Sports Village reads: "The RFL will await reports from the stadium, the police and the two clubs before deciding what action to take.
"The behaviour of the vast majority of fans was exemplary and the incident was not what is expected from rugby league supporters.
"This should not detract from two very successful semi-finals."
The RFL's chief executive, Nigel Wood, said: "The sport has every right to be disappointed with the behaviour of a minority of Widnes fans.
"We will work with the clubs to identify any supporters who encroached onto the pitch. There is no place for such behaviour in rugby league."
Widnes have asked supporters to report what they had seen via a special email address, firstname.lastname@example.org.
The chief executive of the Vikings, James Rule, said in a statement on the Widnes website: "It's evident from the overnight response that our genuine supporters are as disappointed and frustrated by the scenes as everybody is within the club.
"We've had an overwhelming response and the information we have received will be invaluable in conducting a thorough investigation."
The Widnes Vikings issued an apology earlier today to the sport of rugby league, the BBC and the partners of the Challenge Cup, Tetley’s, for the "disgraceful scenes".
A Greater Manchester Police spokesman said: “At the end of the Castleford Tigers v Widnes Vikings Challenge Cup semi-final at Leigh Sports Village, a minority of fans from the Widnes section invaded the pitch.
“Supporting stewards, officers from GMP ensured the supporters left the pitch and made their way out of the stadium.
“Minor damage was caused to seating in the stadium, pitchside billboards and other signage.
“One woman suffered a twisted ankle but there were no serious injuries and no arrests were made.”