A 39-year-old woman and a 50-year-old man, who are yet to be formally identified, were found inside a home in Mount Waverley, in Melbourne's southeast, on Monday night.
Police received a call from a concerned neighbour at 9.20pm after hearing yelling coming from the property, homicide squad detective Dean Thomas said on Tuesday.
A second call was made, which suggested it was "more urgent", and officers arrived at 9.50pm to find the two bodies.
Local police and detectives were able to identify a suspect, a 34-year-old man. He was arrested at Westall Railway Station about six kilometres from the location, with two large dogs, at 1.40am on Tuesday.
Investigators believe he arrived at the home before an altercation broke out, leading to the deaths of the man and woman, believed to be from Mount Waverley.
Police were still piecing together the connection between the arrested man and the deceased, but it is believed he knew the male occupant at the address.
"We've still got to link that up and, obviously, when we talk to him during the course of the day, that will become more obvious to us," Det Insp Thomas told reporters.
"We are not looking for anybody else in relation to this incident."Â
He said investigators were still examining the crime scene and the extent of the injuries to the deceased, saying weapons were used but not a gun.
No one else is believed to have been at the address during the incident, nor was it a robbery.
Graffiti seen spray-painted on the side of the home and along a wooden fence, reading "Enough is enough" and "Karma", is being investigated by detectives.
Counselling and support will be offered to residents but Det Insp Thomas reassured the community the incident was contained.
"It appears to be a targeted attack ... It does not appear to be a random attack," he said.
