Police are investigating after two people were killed and another two left hospitalised by a suspected poisoning in Victoria.

It is understood two men and two women became ill after eating a meal at a home in Leongatha, in the state's Gippsland region, on July 29.

Police were told a 66-year-old woman and a 70-year-old woman, both from Korumburra, died in hospital on Friday.

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The two other people, a 70-year-old man and 68-year-old man, remain in hospital.

"At this time the exact circumstances are still being established and it is not known if the matter is suspicious," Victoria Police said in a statement.

"The investigation into the incident remains ongoing and police will liaise with the Department of Health in relation to the matter."

The health department said it is investigating the incident.

"The Department is aware of the situation and our investigations are ongoing," a spokesperson told 9news.com.au.

"We extend our deepest condolences to the patients' family for their loss."

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