A 15-year-old boy remains in a serious but stable condition after being stabbed at Caves Beach on Saturday night.
The Windale boy was knifed in the abdomen following an argument with another teenager at a beach party at Spoon Rocks.
Following the fight the alleged assailant and several other party goers fled from the area.
Lake Macquarie police set up a crime scene and seized several items for forensic analysis.
Police are continuing inquiries in a bid to identify the culprit and are appealing for anyone with information to contact Crime Stoppers on 1800 333 000.
