Unknown perpetrators killed the German researcher Bernard von Bredow and his daughter in the south of Paraguay.
The bodies of the sixty-two-year-old and the 14-year-old girl were discovered by a friend in the family home around 30 kilometers southeast of the capital Asunción, TV stations reported.
The Foreign Office confirmed the deaths of two Germans on Tuesday.
The incident occurred on October 22nd.
The police assume that robbery is a possible motive, local media quoted the investigators as saying.
The perpetrators cut the fence around the property in Patiño near the town of Areguá, then waited briefly in the bushes and finally broke into the house, said the head of the homicide squad, Commissioner Hugo Grance, on the NPY TV channel.
The house had been searched.
"We can assume that the perpetrators thought there was a lot of money to be found."
Both victims died from gunshots, presumably from the same weapon, said the medical examiner in charge.
The father was killed with a shot in the neck.
"There are indications that he was previously tortured because he has injuries to his face." His daughter was found in a bathtub filled with water.
Blood stains were found all over the house.
Bernard von Bredow and his daughter emigrated to Paraguay four years ago.
At the age of sixteen he discovered a mammoth skeleton in his home town of Siegsdorf in Upper Bavaria.
The archaeologist was one of the founders of the prehistoric museum there.