A 36-year-old man was found seriously injured inside a home on Victoria Drive in Thomastown about 8.40pm.
Police were called to the scene and performed CPR on the man, but he died at the scene.
A 45-year-old man was arrested at the home and remains in custody.
Investigators are also searching for a second person in relation to the alleged stabbing.
Victoria Police said the alleged stabbing “appears to be a targeted attack” in the early stages of the investigation.
Homicide detectives are on the scene.
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