Police have arrested four men and seized more than a dozen motorbikes amid a major investigation into a social media event at Mayfield.
Newcastle and Lake Macquarie police, backed by the dog squad and the Northern Region Operations Support Group, carried out raids across the Hunter on Tuesday, July 14.
Police seized 18 motorbikes, helmets, clothing and electronics during searches at Fletcher, Wallsend, Lambton, North Lambton, Toronto and Fullerton Cove.
Police arrested two teenagers, aged 18 and 19, and two 21-year-old men. They were taken to Waratah Police Station.
They were each charged with rioting, being in a group of people using violence to cause fear, destroying or damaging property, and driving recklessly or furiously.
They each face various other charges. Among them, 19-year-old Robert Gordon is accused of assaulting with the intent to rob, and one of the 21-year-olds, Jayden Patrick Moon, allegedly intimidated police.
Gordon was refused bail in court on Wednesday and will remain behind bars ahead of his next court date. Moon was granted conditional bail.
The 18-year-old, Jayden Stowe, and Edward Whitton, 21, were granted conditional bail in court on Tuesday.
Gordon, Moon, Stowe and Whitton were not required to enter pleas and will face Newcastle Local Court at a later date.
Police have now seized 25 unregistered motorbikes and arrested eight people under Operation Horizon.
Newcastle City Police District commander Kylie Endemi said excellent and tireless police work had led to the breakthroughs.
Investigators have been well-resourced, combing through footage, and have been supported by members of the community providing information.
"From day one, we made a promise to the community that we would investigate this matter relentlessly, these arrests and our earlier arrests, are proof of that commitment," Superintendent Endemi said.
"We will continue to gather evidence and, where we can, we will bring further offenders to justice."
The operation was launched to investigate an event promoted on social media by streetwear brand Bad Apples at the skate park at Dangar Park on Sunday, June 14.
Police attended about 1pm, including officers from the riot squad and the PolAir helicopter, after reports a large group had gathered.
Officers found up to 200 people had converged on the park, where Bad Apples was promising cash and merchandise giveaways.
Police allege up to another 40 people were riding unregistered trail bikes in parkland and on surrounding streets.
Officers closed nearby streets to restore order.
"The community felt as strongly as we did in terms of this behaviour, how dangerous it was and the risk it posed to public safety," Superintendent Endemi said.
"What we have found during the course of our investigation is certainly evidence in relation to other offences as well that we will allege have occurred, and we have charged those offenders with those relevant offences."
Police said the investigation is ongoing and "all aspects" of what occurred are being investigated. It's understood that includes the organisers behind the event, who allegedly failed to cooperate with police on the day.