An 18-year-old man was attacked with a machete when a gang of gatecrashers stormed into a house party in Greenwood last night.
A police spokeswoman said officers had been called to the home in Cypress Court after they received reports of gatecrashers trying to force their way into the party about 10pm.
A fight broke out between partygoers and the gatecrashers, and the victim, who was invited to the party, was repeatedly hit to the head with a machete. He suffered deep cuts to his head and was taken to Sir Charles Gairdner Hospital.
Earlier in the night, police were pelted with rocks and bottles as they tried to break up a wild party in Kelmscott. Police were called to the corner of Arbour Place and Cammillo Road about 9:45pm after reports of about 100 people fighting in the street, having spilled out from a party at a home on Arbour Place.
A total of 24 police vehicles attended and officers were pelted by projectiles.
At 11pm in Secret Harbour police were again called to a house party after reports of gatecrashers armed with baseball bats trying to force their way into the celebration.
The spokeswoman said it was believed there was an altercation between the people invited to attend the 16th birthday party and the gatecrashers. No one was injured but a letterbox of a nearby home was smashed.