An investigation is underway after the bodies of two elderly men were found inside an inner city house in Sydney.

The men were found in separate rooms of a house on Cleveland St, Surry Hills, at about 2pm on Thursday.

Police believe they died at different times within the past month.

Their identities are yet to be confirmed, but the men are believed to be aged in their 70s and 80s.

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A 63-year-old woman who lives at the property has been spoken to by detectives.

As investigations underway, police are urging anyone with information about the incident to come forward.