Barnsley and Leeds state they are»working together» to assess the audience difficulty which marred Sunday’s derby at Oakwell.
South Yorkshire Police are known to have started an investigation after the arrest of three people on suspicion of public order offences and one for attack.
A spokesperson for the two clubs said:»Barnsley Football Club and Leeds United Football Club are greatly disappointed with reports of violence in Sunday’s match and will be working with each other to evaluate the issue.»
Leeds fans battled with stewards and, from the stand, fighting broke out in a separate event.
Leeds scored two goals in the last eight minutes to clinch a 2-0 triumph and return.
The scoring opened in the 84th minute.