Three gatecrashers breaking into a birthday party allegedly stabbed a man

A reveller at a suburban house party was allegedly stabbed in the back with a knife by a group of gatecrashers. 

The melee broke out at a house in Rouse Hill, in Sydney’s north west, at about 9.30pm on Saturday night.

Dashcam footage captured three uninvited men brandishing shovels sneaking through the side gate at the 22nd birthday party.

A kitchen knife was found on nearby Caddies Boulevard on Sunday morning

A dozen partygoers allegedly tried to move the trio on before making their way on to the driveway.

A young man was then allegedly stabbed before concerned neighbours rushed to his aid.  

‘There was blood everywhere as well, towels mopped up with it as well,’ witness Zac Colman told 9News.

Police allege the men had been kicked out of another house party a street away from where the incident took place.

A kitchen knife was found on nearby Caddies Boulevard on Sunday morning.

Police are trying to determine if it was the weapon used in the alleged attack.

Officers are also looking into dashcam footage that captured a white sedan leaving the scene which was believed to have been driven by the alleged attackers.  

‘A man could have lost his life because some fool has decided to take a knife to a party,’ Detective Inspector Chris Laird said.

‘It’s unacceptable if it had happened in the street but it’s even worse that these lowlife scumbags have come into somebody’s house and brought a knife.’

Inspector Laird said the three men were of pacific islander, African and European descent.  

‘We’ve got some names so you can come to the police station now, or we’ll come to your house tonight, the choice is yours,’ Inspector Laird said. 

Officers are also looking into dashcam footage that captured a white sedan leaving the scene which was believed to have been driven by the alleged attackers