Police were called to a Meriton building site on Sexton Avenue in Castle Hill about 7am, after reports that up to 50 people had become involved in the brawl.

Video of the struggle showed the two groups trading blows, with one man appearing to be kicked in the head with a steel-cap boot, and another beaten on the head with a hard-hat.

By the time police arrived, the fight had broken up.

Paramedics took a 43-year-old and a 55-year-old man to hospital with minor injuries, and they have both since been released.

Today, two men were arrested at Castle Hill Police Station at about 11am.

They have not been charged, and police said they are trying to identify several other people involved in the fight.

In a statement yesterday, Meriton said the contractors involved in the fight had been fired.

“Meriton promotes safety and does not condone any violent or threatening behaviour on its job sites, whether employees, subcontractors or visitors,” it said in a statement.

“No direct Meriton employees were involved in the incident that took place today on the street, outside of its Castle Hill construction site.

“Appropriately, the local police were called who have since intervened and we have ascertained that there were no serious injuries.

“The contractors involved in the fight have been immediately terminated.”