Two teenage boys have been arrested in connection with a violent incident inside a shop in Churchill Square, Brighton.
Meanwhile, Sussex Police has asked the public not to share video footage of what happened, to help protect their investigation.
Officers reported being called to the incident, which they described as an 'altercation', at a shop in Churchill Square at around 3pm on Thursday (14 December).
Three boys and a man were treated at the scene for minor injuries.
Following enquiries, a 14-year-old boy from Telscombe Cliffs and a 16-year-old boy from Eastbourne were arrested on suspicion of affray.
They remained in police custody by Saturday afternoon.
Investigators added that enquiries were continuing to find others involved in the incident.
Police increased their presence in the area, in what they described as an attempt "to ensure the safety of the public, with a continued visibility to provide further reassurance".
Chief Inspector Andrew Saville said:
"Violence and anti-social behaviour such as this is unacceptable and will not be tolerated.
"We are aware that a video of the incident is circulating on social media and we ask the public to refrain from any speculation as this could undermine the ongoing investigation.
"Anyone who witnessed the incident or has any information which could help police with their enquiries, can report online or by calling 101 quoting reference 757 of 14/12."