The family was in the garden of their home in the village of Saint-Herbot near Quimper in Brittany on Saturday night when their neighbour appeared with a firearm, according to the initial investigation.

At around 10pm, law enforcement officials intervened “following gunfire”, Quimper public prosecutor Carine Halley said in a statement on Sunday.

Brittany shooting: What we know so far about the victims 

The 11-year-old was found dead at the scene, while her father had sustained life-threatening injuries, according to the magistrate.

The mother’s life was not deemed to be in danger and a second child was unharmed but “in a state of shock”, prosecutor Halley said.

The shooter was identified as a 71-year-old Dutch pensioner.

While police were still trying to determine the motive for the shooting, “it would appear that there had been a dispute between the two neighbours for several years over a plot of land adjoining the two properties”, Halley added.

A police source told AFP that the neighbour had fired his rifle through a hedge before retreating to his home with his wife.

Both the neighbour and his wife have surrendered to authorities and been arrested.

The public prosecutor’s office has opened an investigation on charges of voluntary manslaughter of a minor and attempted voluntary manslaughter.