A village in northwestern France where a Dutch retiree allegedly shot dead an 11-year-old British girl and gravely wounded her two parents was in shock Monday over the "abominable" violence.

Sitting in the Monts d'Aree hills in western Brittany, the isolated hamlet of Plonevez-du-Faou had been home to the British family since 2019.

The girl and her younger sister were playing on a swing as their parents barbecued nearby when a neighbor opened fire with a shotgun through a hedge, the BBC reported Monday. 

The girl's sister ran to another neighbor's house, shouting, "My sister is dead, my sister is dead," the BBC said.

The suspect, described as a 71-year-old Dutch national, reportedly shut himself in his house before eventually surrendering to police. He was arrested along with his wife, the BBC reported. 

The UK Foreign, Commonwealth and Development Office told the BBC it was providing assistance to a British family.

The father, Adrien T., began clearing vegetation and detritus from his land, formerly the site of a sawmill — drawing the ire of the neighboring couple, aged 70 and 69, known locally as "the Belgians," although prosecutors say they had Dutch nationality.

With the neighbors bothered by the noise of Adrien's chainsaw and by the fact their house was now visible from the road, the town hall initially stepped in to mediate.

"We could see (the neighbor) was griping but there wasn't anything at all alarming" about the dispute, Mayor Marguerite Bleuzen said.

"It was (Adrien's) land, he can do what he likes with it."

"It's a tragedy," said Kim McKanney, 64, a British pensioner out with her poodle a few hundred meters from the crime scene.

"I'm shocked and upset that a family has been affected like this and a child killed in a little village which is so quiet, peaceful and friendly," she added, looking close to tears although she did not know the victims.

"You might expect it in a city but not here."

Aside from the friction with their neighbors, the British family quickly put down roots in their village, sending their daughters to nearby schools.

Described as "a lovely person," the mother worked as a home carer for elderly people.

The family also helped organize village parties, even allowing visitors to park on their land.

"They're very nice, very kind, always happy to help," said a close neighbor in his 80s who asked not to be named.

He drew a contrast between the family and the suspected shooter, who he said he had "never seen face-to-face" since the couple arrived in 2017.

"We never saw them. No contact, nothing at all," added the elderly man, who said that "nothing has ever happened here" in all the years since he arrived in 1948.

"No one knew" the suspect, mayor Bleuzen agreed, who described his appearance when arrested as "a little guy with long white hair, a long beard, and completely wild-looking".

"What on earth could have been going on in his head?" she wondered.

Saturday's multiple shootings were "appalling, abominable," said one local resident as she left white roses on the threshold of the British family's home.

The slain girl "was the same age as my grandson, I'm really moved. Who wouldn't be?" she added, herself appearing close to tears.

A source close to the investigation told AFP that a large amount of cannabis had been found in the suspect's home when it was searched by police.

Prosecutors from the nearby city of Brest will hold a press conference later Monday.