The bodies of the 74-year-old retired doctor and her 77-year-old brother, a former university lecturer, were found by the sister’s daughter at the large family home in Gütersloh, North Rhine-Westphalia on December 25th.
Investigators said the house looked like it had been searched.
Police said that both of the victims died from multiple stab wounds and an investigation is now underway.
Meanwhile in Pritzwald, Mecklenburg Western-Pomerania, a 64-year-old man allegedly killed his wife on Christmas Eve. The 59-year-old woman was found dead in her flat on December 24th. An arrest warrant has been issued for the husband.
An argument between two men on Christmas Eve in Cologne also ended in a death. A 32-year-old was badly injured in the argument and died from his wounds. His 54-year-old flatmate has been arrested.