At around noon on Monday, an apartment block in the normally peaceful town of Alt-Heerdt in Düsseldorf echoed with the sound of gunfire.
An argument between a mother and her 18-year-old daughter had escalated rapidly before the 44-year-old woman had allegedly reached for a weapon.
She then reportedly shot the teen five to six times, with a small-calibre target pistol.
With life-threatening injuries, the teenager dragged herself out of the second-floor apartment and onto the street, where a nearby construction worker gave her first aid and notified emergency services.
Meanwhile, the mother barricaded herself in the apartment.
By the time police officers got to the scene, the 44-year-old was in critical condition.
After locking herself in the apartment, she had shot herself in the head.
Both mother and daughter were rushed to hospital, where the older woman later died of her injuries.
The daughter remains in intensive care, but is "on the road to recovery", police said on Tuesday.
A member of the Düsseldorf Shooting Club, the 44-year-old has competed in nationwide competitions, reports Bild.
She owned a valid gun license allowing her to keep the weapon at home.
Argument was about Australia visit
"The argument centred around a long-term visit abroad that the daughter had planned, and which she planned to set off on that day," a police spokesperson said on Wednesday.
The 18-year-old supposedly wanted to travel to Australia, Bild reports.
"A family drama like this doesn't arise out of nothing," criminal psychologist Rudolf Egg told Bild. "Things must have been building up for a while."
The trip abroad was likely the tipping point for the mother, Egg explained.
"Great closeness, affection and love can turn instantly to hatred, anger and violent outbursts," he continued.
"Time and time again, we see that the people we love the most are also the ones we can hate the most."