Police said the family are from Holland but used the house in Germany as a 'chop shop' to dispose of their victims, who they killed with an icepick and a semi-automatic gun.
An international manhunt is now underway after two of the killers went on the run in South America.
The horror house was only uncovered after neighbours complained of a 'peculiar' smell coming from the property in Tuddern, in Germany.
And police have not ruled out the possibility that there are more victims as they collect human remains from the sewerage system of the small town.
Revenge was the motive for the murders, said police.
Although a mother and her two adult sons have been arrested her husband and adult daughter have fled to South America, German police believe. Read More