La Mare De Carteret fight: Police appeal after fight
Police are appealing for witnesses to come forward following "widespread disorderly behaviour" involving about 200 people.
Fighting was reported at La Mare De Carteret playing fields at 17:50 BST on Sunday.
Insp Liam Johnson, of Guernsey Police, said in a press conference on Thursday that four people had been arrested.
He added that the fighting had been arranged through social media and that enquiries were ongoing.
Police said one person was taken to hospital with minor injuries following the incident.
"This gathering escalated into a number of fights and widespread disorderly behaviour," Insp Johnson said.
"It's clear there are a group of young people who seem to be communicating via social media and it could be through social indifference or other social factors with these young people leading them to come together."
Police said they did not want to "demonise young people" in Guernsey but there was "a clear issue with a minority" that needed to be addressed.
They asked for anyone with any information about the incident to contact them.
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