A picture of a man has been released in connection with the disorder at Runshaw College.
Around 12 people arrived in cars at the college site in Leyland on Monday 4 March around 4pm for a pre-arranged fight.
Lancashire Police placed the college and Leyland Station on lockdown following the incident in which a 17-year-old boy received a cut to his arm with a knife.
Police have now released the CCTV picture of a man they wish to speak to.
Detective Constable Terry McKibbin, of Chorley CID, said: “We are continuing to investigate disorder close to Runshaw College in Leyland.
“While we have made a number of arrests, we’re keen to identify this man in connection with the incident.
“I would urge anyone who knows who this is to come forward and contact police immediately.
“Any information provided to police will be treated in the strictest confidence.”
Read more: Police seek video footage of the Runshaw College fight
Seven people were arrested by police in connection with the disorder and have been bailed.
Anyone with information is asked to call police on 101 quoting log 0933 of March 4.
Alternatively independent charity Crimestoppers can be contacted anonymously on 0800 555 111 or online at crimestoppers-uk.org.
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