A child's first birthday celebrations have ended in tragedy after a fight broke out and led to the deaths of two family members.
Emergency services were called to reports of an altercation at a home in Clyde North, in Melbourne's outer southeast, at 9.30pm on Thursday.
Two men, aged 23 and 54 from Seaford, were found with stab wounds and treated by paramedics but both died at the scene.
Superintendent Janet Stevenson said about 20 people were attending a birthday party at the home when an argument started, before it turned into a brawl and spilled out into the street.
The two men were fatally stabbed with what Supt Stevenson described as a "sharp edged weapon".
She said police had spoken to people who attended the party, including family and acquaintances, but some had fled the scene before officers arrived.
"This was just a private birthday party that should have been a celebration and unfortunately, a tragic result," Supt Stevenson told reporters at the scene.
Supt Stevenson asked anyone with information to come forward and for those responsible to hand themselves in.
"It's in everyone's interest, especially for this family who's now grieving after losing two of their members," she said.
"Clearly, there's something going on here that is just dreadful, but it's not a threat to the rest of the community."
She said initial reports that police were searching for a third man were incorrect.
Earlier on Friday, neighbours described their shock at hearing sirens in the normally quiet street.
They told AAP there was a party at the home on Thursday evening, which may have got out of hand.
"It’s very scary," one neighbour, who didn’t want to be named, said.
"We actually watched as the police arrived, for quite some time, but police told us to stay inside our homes for our own safety.”
The man and his wife were working from home on Friday morning, as police try to piece together what happened.
Another neighbour, who had to be escorted to her home through police tape, said she wasn't surprised that something like this had happened.
The estate, which is off Thompsons Road, is relatively new with the first residents moving in around seven years ago, neighbours confirmed to AAP.
Numerous forensic police and homicide detectives arrived shortly before 9am and a police officer at the scene said they are expected to be there for most of the day.
Two SES tents remain in the street, one covering what is believed to be a body.
