A man has died and four others have been arrested after a brawl broke out at a house party in Sydney’s southwest last night.

The NSW Police Riot Squad, the Dog Unit, the Rescue Squad as well as Campbelltown police were called to a house in Ingleburn, after reports of an altercation involving a large group of people.

According to police, the brawl is believed to have begun during a party at a home on Chester Road before spilling into the street, with more people arriving in vehicles, some armed with baseball bats.

The man, who is yet to be identified, was treated by paramedics at the house for serious injuries but was unable to be revived and died at the scene. It is not clear how the man died.

A crime scene was established and four men have since been arrested and are being questioned by police at Campbelltown Police Station.

Chester Road will be remained closed between Percy Street and Gertrude Avenue as the scene is examined.