Walter Luebcke, who led the Kassel regional administration in central Germany, was shot dead at his home on June 2. A 45-year-old German man with a string of convictions for violent anti-migrant crimes, Stephan Ernst, was later arrested as the alleged killer. He first admitted to carrying out the killing but later retracted his confession.
Authorities are also investigating two other men, who are accused of accessory to murder for allegedly helping Ernst get the murder weapon. Luebcke was known for supporting the welcoming policy toward refugees that Merkel adopted during an immigration influx in 2015.