Police and prosecutors are investigating a connection between the shooting of a 36-year-old in Dormagen in North Rhine-Westphalia and a shot at a mother and her daughter in Rhineland-Palatinate.
The alleged perpetrator apparently committed suicide shortly thereafter.
The 36-year-old was shot dead in a kiosk in Dormagen south of Düsseldorf on Friday.
The alleged perpetrator, a 55-year-old Kosovar, was discovered a few hours later on the side of the road about a kilometer away with a fatal gunshot wound to the head.
According to initial findings, the man had pointed a firearm at himself.
He died in hospital a short time later.
Both men, the 55-year-old and the 36-year-old, were no strangers to the authorities.
According to their own statements, the public prosecutor and the police also have indications that the 55-year-old previously shot two other people in the Westerwald in the Rhineland-Palatinate district of Neuwied.
The mother and her adult daughter were discovered on Friday near Breitscheid, around 90 kilometers from Dormagen, with gunshot wounds.
They are said to be receiving medical treatment.
The crime is classified as attempted homicide.
A spokeswoman for the Düsseldorf public prosecutor said on Sunday that further information on the case would probably not be available until Tuesday.