Four people are in hospital, one in a critical condition, after a frenzied stabbing attack in Melbourne.

Three underwent surgery and another is under police guard following the incident in Sunshine North on Thursday.

Police were called to a home just after 4pm where they found two women, aged in their 30s and 60s, and a man in his 30s with significant stab wounds.

Another man at the property, aged in his 20s, sustained injuries to his upper and lower body and is in a stable condition under police guard in The Alfred hospital on Friday.


"The investigation is in its early stages at the moment, but we want to reassure the public that it's been contained and there is nothing to worry about," Acting Inspector Cameron Reinke told reporters, adding they were all known to one another.

The older man, who suffered upper body injuries in the attack, is in a critical condition in The Alfred.

The two women, who also sustained upper body injuries, were taken to the Royal Melbourne Hospital in a critical condition on Thursday, but have improved.

The woman in her 60s is in a serious condition and the woman in her 30s is stable.

No charges have been laid.

Neighbours at the scene on Thursday said they were surprised something so horrible could have taken place in the usually quiet street.

Others said they heard screams before emergency services arrived.

Neighbour Peter Pham said the house where the incident occurred was normally trouble free.

"They're usually pretty quiet. I'm not really close with them but they seem OK," he said.

"There are no problems at all. You never see any issues over there. Nothing unusual."

At least three children, a girl and two boys lived at the house with their father and another man, possibly the children's grandfather, Mr Pham said.