An elderly woman allegedly shot and killed her neighbour in a heated argument about his barking dog, before turning the gun on the victim's wife.
Silvana Erzembergher, 71, is said to have shot Luigi Casati, 62, three times in the chest outside their apartment block in Treviglio, northern Italy, last month.
His horrified wife, Monica Leoni, 57, rushed to his aid after watching the events unfold from her balcony.
But Erzembergher allegedly shot her twice in the leg using a powerful Magnum-style revolver.
Horrifying phone footage of the aftermath shows Mr Casati's body sprawled on the tarmac while his wife sits beside him cradling their pet dog.
Erzembergher, with her grey hair in a neat bun, was then allegedly seen walking around waving the deadly pistol.
The double shooting took place at around 7.40am on Thursday, April 28.
Continuous threats: 'I'll kill you all'
Erzembergher, a retired peddler, had moved into the housing estate around a decade ago, and neighbours said she picked fights with everyone.
One neighbour reported that she would constantly ring residents' doorbells for no reason other than to annoy them – even in the middle of the night.
Ms Leoni reported her to police after she allegedly chased and beat her with a stick.
The woman was believed to have harboured a special grudge against Ms Leoni, her husband and their pet dog, Chanel.
She is said to have frequently complained about Chanel's barking. But other neighbours said the pooch was quiet and well-behaved.
Residents said that whenever Erzembergher had a problem with a neighbour, she would threaten them, telling them she had a gun in her flat.
In the days leading up to the fatal shooting, she had reportedly shouted from the middle of the estate's forecourt: "I'll kill you all."
Erzembergher shot Mr Casati while he was on his own on the apartment block forecourt where he was pronounced dead
Ms Leoni was later rushed to hospital and is now believed to be recovering from her injuries.
The suspect's firearm – which she had a licence for – was confiscated and, after falling ill, she was also taken to hospital, where she remains under police guard.
When she recovers, she will be remanded in custody in Bergamo and will answer to charges of aggravated voluntary murder and attempted murder.
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