A missing woman has been found critically injured in hospital just four days before dying from her injuries, sparking a major police probe.

The woman, aged in her 60s, was first reported missing by a concerned neighbour in Melbourne’s south-east on June 14.

The neighbour had seen the woman with an unknown man outside her home on Marna Court in Noble Park a week earlier, but had been unable to contact her since.

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Only two days after the woman was reported missing, police found her in a critical condition in Dandenong Hospital, with “injuries that appeared consistent with being seriously assaulted”.

Officers were able to speak with her in the hospital, however, they confirmed she died from her injuries on Friday.

“At this time, the exact circumstances surrounding the incident which led to her being injured are still being determined,” police said.

“Detectives from the Homicide Squad are investigating, and her death is being treated as suspicious.”

Police said the woman’s next of kin have yet to be notified of her death.

“(We) have spoken with a 62-year-old Endeavour Hills man in relation to the incident, however he has been released pending further enquiries,” they said.

Police confirmed the man and woman were known to each other.

“Detectives are keen to speak to anyone who may have further information about the circumstances leading up to the woman’s death.”

Investigations are ongoing.