Police were at the family's house to break up a dispute the day before the violence. Suspect had no criminal record and testified when the arrest warrant was issued.
The family was apparently known to the police; officers rang the doorbell. The parents, aged 58 and 61, died in the apartment building in the Waldshut district in Baden-Württemberg. The 34-year-old brother died in hospital as a result of his injuries. The sister suffered serious stab and cut injuries in the attack.