Police are appealing for witnesses after a 12-year-old girl and a footballer were injured when flares were thrown into a stadium during an FA Cup match.
A group of protestors started throwing flares inside the stadium during the clash between Bury AFC and North Shields on Saturday, Greater Manchester Police said.
The incident, which happened around 20 minutes after kick-off, left a player and a child spectator with minor injuries, the force said.
The match at Stainton Park, which was being shown live on television, was paused after the incident.
Greater Manchester Police said it was an "isolated incident" and not connected to other reports of fireworks "being used in an antisocial manner" elsewhere in Bury.
The force said enquiries are ongoing to identify the men involved and urged anyone with any information to get in touch.
Protests were expected to take place this weekend against proposals to merge Bury's two football clubs – Bury FC and Bury AFC.
The incident at Stainton Park also comes just days after Greater Manchester Police vowed to take action against fans seen using flares during Southampton's clash with Manchester United the previous week.
The warning came after photos shared online showed a flare being used by what appeared to be Manchester United fans at St Mary's.
Following the appeal for information in relation to the incident on Saturday, Chief Inspector Samantha Goldie of Greater Manchester Police's Bury Division, said: "Whilst we anticipate protests taking place and facilitate them where possible, we absolutely do not tolerate violence.
"This is a public event and ultimately we want everyone to be safe and have an enjoyable time. Thankfully this reckless and dangerous action by a few did not result in serious injury.
"We are keen to speak to anyone who might have more information that could help identify those involved. If you witnessed this incident, or have footage, please share it with us as soon as possible."