A young woman has been remembered as a "beautiful soul" after her body was discovered inside her family home in Melbourne's north-east.
A 35-year-old man was arrested in the early hours of Monday, shortly after Celeste Manno, 23, was found dead on Umbria Road in Mernda about 4.10am.
Celeste Manno (inset) whose body was found in her home in Mernda on Monday.
The man was taken to hospital with non-life-threatening injuries where he remains under police guard.
Police said in a statement that they believe the man and Ms Manno were known to each other.
Detectives are investigating whether she worked with the man at some stage. A relative at the scene said the pair did not know each other well.
Flowers were left outside Ms Manno's home where crime scene investigators remained for most of the day.
What appeared to be blood could be seen on the side gate of the home.
At the scene, distraught family and friends of Ms Manno gathered near the police tape throughout the morning, crying, hugging and consoling each other.
One woman collapsed to the ground and cried as she repeatedly said "how is this possible?" and "I can't believe it".
Close friend and work colleague Bertine Rashou said she had been shocked by the news.
"She was the most beautiful soul I have ever come across. I can’t imagine why anyone would want to hurt her," she told The Age.
"She was kind, loving and a great friend to many. A gorgeous young soul that was taken way too soon."
Homicide squad detectives and forensic officers examine a car at the Mernda police station.Credit: Jason South
Friend Maddi Johnston said she was "the most loving, generous and kind-hearted friend to everyone around her".
"I will forever cherish the memories that we made and for the friendship that we gained," she said. "This world can be cruel, and you did not deserve this at all."
Ms Manno studied criminology and psychology at RMIT, according to her social media profiles.
She worked at a Mill Park call centre run by Serco Asia Pacific. The company's chief executive Peter Welling said they were continuing to assist Victoria Police as they investigated the "circumstances of this heart-breaking tragedy".
"I was devasted to learn earlier today of the tragic death of Celeste Manno, a highly respected team leader at our Mill Park, Melbourne centre. The entire team at Serco Asia Pacific extends our deepest sympathies to her family, friends and colleagues," he said in a statement.
"Celeste has been a warmly regarded and valued member of our team. Her sudden and tragic loss has deeply affected all of us at Serco and is particularly heart-breaking for our colleagues who had the privilege to work with her at our Mill Park centre."
On Monday morning, police set up a second crime scene at the Mernda police station – less than two kilometres from Ms Manno's home – where forensic officers spent the morning examining a small blue Peugeot.
CCTV footage from one nearby home showed the Peugeot found at the police station leaving Ms Manno's street just before 4am. An ambulance then arrived minutes later.
An SES tent was erected over the car while officers examined it. The tent was removed just before 11.30am.
And a 50-year-old man was found dead inside a Palmyra Court home about 11.30am at Greensborough in Melbourne's north-east.
Homicide detectives are investigating the incident, which is not related to Ms Manno's death.
A woman aged in her 80s was also found inside the home and was taken to hospital under police guard where she remained on Monday night.
"It is believed the pair were known to each other," a police spokeswoman said.
Anyone who witnessed the incident or with information is urged to contact Crime Stoppers on 1800 333 000 or visit www.crimestoppersvic.com.au
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