Homicide Squad detectives are investigating after a woman was located deceased in Deer Park last night.
Emergency services were called to reports of an unresponsive woman at a property on Stevenston Street about 11.45pm on 17 July.
The 51-year-old Deer Park woman was declared deceased at the scene.
A 30-year-old man, a 26-year-old woman and a 38-year-old woman - all from Deer Park - were arrested at the property.
The man and 26-year-old woman were interviewed and released without charge.
The 38-year-old woman was taken to hospital where she remains under police guard.
The exact circumstances surrounding the death are yet to be determined and investigations remain ongoing.
It's believed the parties are known to each other.
Anyone with information that could assist investigators is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au
