It only ended when they called the riot police in.
Rooms were trashed, neighbours terrorised and heavily-armed police pelted with rocks after they rushed to an out of control house party in Melbourne early this morning.
One of the witnesses likened it to a "war zone".
Officers were attacked as they attended a property at Attunga Grove in Werribee — rented out on short-stay website Airbnb.
Police were called about 3.30am today but retreated under a barrage of flying rocks and metal poles pelted by partygoers.
They returned with the riot squad to break up the party, with one officer sustaining an elbow injury as the party turned even more violent.
When the drama cleared, a trail of destruction remained.
Pepper spray residue, blood splatter, graffiti and broken glass were left in the extensively-damaged three-bedroom property, while some walls had holes kicked in them.
Terrified neighbours cowered in their homes at the height of the violence, trying to avoid the gangs, who used poles to smash car windows and tried to kick down doors.
"It was terrifying ... I grabbed my young daughter and went to the back room so that way, if they got in, we'd be harder to get to," neighbour Kristy told AAP. "They were looking for trouble."
Friday dawned to reveal cars along the street with smashed windows and rocks littering the road.
Gang links to riot
Neighbours say up to 40 youths from the house started roaming the streets, throwing rocks and smashing cars.
Neighbour Chantelle said the youths were wearing basketball jerseys and police were clearly outnumbered.
"As soon as they started throwing rocks at the police they thought they could do anything and it started getting worse," she said, adding there had been troubles a night earlier.
"They treat it as a game," Chantelle said of the rioters.
"They knew there were issues the night before; why would they only send two police officers to start with?" Kristy asked.
It's understood two gangs of African youths, one known as Westside Crew and another as Menace to Society, were involved in the riot.
Four girls rented out the house and it's understood word spread of an open house during a basketball tournament this week.
Police were initially called to a report of two women being assaulted, but the violence escalated. No arrests were made.
"This behaviour is completely unacceptable," police Inspector Martin Allison said.
"The message we need to get out to the community and particularly the people who behaved so appallingly is that they'll be held accountable."
He would not comment on whether the incident was linked to a nearby South Sudanese basketball tournament, which wrapped up on Tuesday.
The house was listed for rent with the warning "no parties".
Neighbours of the violent house party may sleep easier tonight: AirBnB has banned the troublesome tenants and the house listing has been removed.
A spokesman for Airbnb said: "Airbnb has zero tolerance for this kind of behaviour, which goes against everything our community stands for. We have permanently banned these individuals from our platform and are fully supporting our host.
"Our team has also reached out to local law enforcement to offer our assistance with their investigation. We hope justice is served quickly. To date, there have been over 260 million guest arrivals in Airbnb listings worldwide and negative incidents like this are incredibly rare."
The company offers a "Million Dollar Host Guarantee" which covers listings for up to $US1 million ($A1.4 million).