A man was punched to the ground and repeatedly kicked by a group of individuals in the Asda car park in Bolton Street on Friday (December 11).
The man reportedly did not receive any serious injuries, but officers say the group responsible were all wearing dark clothing, face coverings and had their hoods up.
Police say the level of violence intensified when a group of men were attacked with baseball bats, sticks and bottles on West Street Car Park the following day (Saturday, December 12).
One of the victims suffered a broken wrist as a result of the attack and the other men involved received "cuts and bruises to the arms and body."
Following extensive CCTV enquiries, officers have identified and arrested an 18-year-old man in connection with the incident on West Street Car Park.
Sgt Harrison, from Chorley Neighbourhood team, said: "Incidents of this nature are completely unacceptable and will not be tolerated.
"Both incidents were completely unprovoked and we are not ruling out that the perpetrators are involved in both incidents.
"We will be conducting a full investigation into both matters."
Chorley Police say they will be increasing patrols in and around town centre following the disorder.
Anyone with any information about either of the incidents has been urged to email [email protected]
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