During New Year's eve, a party was held at a house at Harrington and at about 1am January 1, officers from Manning/Great Lakes Police District received a number of complaints regarding excessive levels of noise coming from the event.

Police attended and directed the occupiers to reduce the level of noise before shutting the party down when those directions were ignored.

Just before 3am, emergency services were called back to the address, following reports an 18-year-old boy had been assaulted.

He was treated at the scene by ambulance paramedics before being taken to Port Macquarie Hospital for treatment. He remains in a serious but stable condition.

Police opened an investigation into the circumstances of the incident.

As inquiries continue, police are seeking assistance from the public and are appealing to those who were at the party and might have mobile phone footage of the incident, to come forward.

Anyone with information that may assist Manning-Great Lakes detectives is urged to contact Crimestoppers on 1800 333 000 or nsw.crimestoppers.com.au.

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