While details are still unclear as to what exactly happened, it is believed that the fire started at the house at about 3.30am on Thursday morning, Pietermaritzburg Public Eye reports.
Unconfirmed reports have suggested that the house was petrol-bombed.
READ MORE: Arson suspected in PTA East house fire
The five deceased members of the Munjra family (first names not released as yet) include the 45-year-old parents, 15-year-old daughter, 10-year-old son and 65-year-old grandmother.
It is believed the family moved into the Larch road home five months ago and one of the members worked at a well-known store in the CBD.
The family are foreigners, and it is believed all five bodies were found on the verandah.
Neighbours were alerted to the fire at about 4am when the fire brigade arrived.
Police spokesman Sergeant Mthokozisi Ngobese confirmed they were investigating arson and murder.
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