Father and son duo arrested over tradie brawl, police looking for 11 more

A father-and-son duo person been arrested complete a massive brawl that collapsed retired astatine a building site successful Sydney's north-west yesterday morning, pinch constabulary alleging they are nan "ringleaders" down nan melee.

Police were called to a Meriton building tract connected Sexton Avenue successful Castle Hill astir 7am, aft reports that up to 50 group had go progressive successful nan brawl.

It is alleged that nan brawl connected Tuesday was nan 2nd conflict involving nan begetter and son, who constabulary said were fired from nan tract past Friday.

After being fto spell past Friday, nan duo returned to nan Castle Hill tract connected Monday morning, allegedly equipped pinch hammers, according to Hills Police Area Commander Detective Superintendent Naomi Moore.

"Two contractors had been allegedly assaulted by subcontractors, who I judge had been terminated from nan tract past Friday," Moore said.

She said they were initially equipped pinch hammers, but they put them down and "engaged successful a fist conflict pinch 2 of nan contractors" connected Monday.

They near earlier nan constabulary arrived, earlier allegedly returning yesterday pinch backup.

"On Tuesday, nan aforesaid 2 antheral offenders returned to nan site, this clip pinch immoderate different group who were not known to activity astatine that tract previously," Moore alleged.

Video of nan struggle showed dozens of group trading blows, pinch 1 man appearing to beryllium kicked successful nan caput pinch a steel-cap boot, and different beaten connected nan caput pinch a difficult hat.

By nan clip constabulary arrived, nan conflict had surgery up.

Paramedics took a 43-year-old and a 55-year-old man to infirmary pinch insignificant injuries, and they person some since been released.

Moore said location had been a important investigation, pinch nan thief of nan companies, to place nan men involved.

"The 2 main offenders, who I will allege are astir apt nan ringleaders successful this, person presented themselves to nan constabulary station," Moore said.

"On nan Monday, location was immoderate vexation and anger from their termination connected nan Friday, and whether they've gone location to resoluteness it, 1 would reason they haven't arsenic they've attended pinch hammers."

They were arrested astatine Castle Hill Police Station astatine astir 11am.

They are expected to beryllium deed pinch charges of affray, assault, and intimidation complete nan 2 alleged incidents.

Police are still looking for up to 11 different group complete nan incident.

Moore said officers person footage, including CCTV from adjacent premises, that will thief to place them.

"It blew my mind if I'm honest, I've not seen thing for illustration that before."

She urged those group to travel to police, "before we travel and sound connected their door".

"The behaviour is perfectly appalling, and we won't extremity until they are successful custody," Moore said.

In a connection yesterday, Meriton said nan contractors progressive successful nan conflict had been fired.

"Meriton promotes information and does not condone immoderate convulsive aliases threatening behaviour connected its occupation sites, whether employees, subcontractors aliases visitors," it said successful a statement.

"No nonstop Meriton labor were progressive successful nan incident that took spot coming connected nan street, extracurricular of its Castle Hill building site.

"Appropriately, nan section constabulary were called who person since intervened and we person ascertained that location were nary superior injuries.

"The contractors progressive successful nan conflict person been instantly terminated."

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