Detectives have been probing violence before, during and after the game between Port Vale and Swindon Town
Three men have been arrested by police investigating violence at a League Two play-off semi-final.
The Staffordshire force said it was probing reports of offences before, during and after the match on 19 May in which home side Port Vale beat Swindon Town on penalties.
Fans invaded the pitch after the game and at the time, Swindon's manager said his players were "physically and verbally abused".
The men, aged 19, 28 and 39, from Stoke-on-Trent, were detained on suspicion of wounding with intent.
Det Insp Andy Bryan said officers had reviewed hours of CCTV, bodycam and TV footage and investigations continued.
He added the force expected to make more arrests, saying "we are working closely with both clubs to help locate those responsible".
Port Vale said it would take the "strongest possible action" against anyone found guilty of being involved "including barring individuals from future games".
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