Trash talking on Facebook sparks father and son stabbing in Sydney brawl: reports

Three brothers have been refused bail after a father and son were stabbed during a massive brawl that was apparently organised over social media.

Five men have been arrested following the fight believed to have involved at least 30 people outside Rouse Hill Town Centre in Sydney's northwest.

Violence broke out at the intersection of Caddies Boulevard and White Hart Drive, in Rouse Hill about 8.30pm on Thursday.

Witnesses have told the media that the father had arranged to confront someone over comments made against his son on Facebook.

The 41-year-old father was allegedly knifed in the stomach, arms and back. His 20-year-old son suffered a single stab wound to the chest.

The pair underwent surgery emergency surgery at Westmead Hospital where they both remain in a stable condition.

It's claimed the attackers were armed with baseball bats, knives and scissors.

Detectives scour the crime scene near the intersection of Caddies Boulevard and White Hart Drive. Photo: 7News

"I saw one of the guys who got stabbed running off but then he collapsed to the floor. The guy who had the knife just went away," a witness told Fairfax.

"There was a lot of blood. The knife was the length from the palm of your hand to your fingers."

Bloodied clothes left on the roadside following a massive brawl in Sydney's northwest. Photos: 7News

A crime scene was established and police have spoken to several witnesses.

Their investigations led to the arrest of five men at a home in Whalan and were taken to Mt Druitt Police Station.

Morning news break - October 10