An 11-year-old British girl was shot dead in Saint-Herbot, a hamlet in Brittany, western France, on Saturday, according to the local prosecutor.

The girl’s parents were seriously wounded in the gun attack. Her 8-year-old-sister escaped and was found “unharmed but in a state of shock,” Quimper prosecutor Carine Halley said in a statement on Sunday.

The family were in their garden when their 71-year-old Dutch neighbor appeared with a firearm and started firing several times in their direction before shutting himself in his house with his wife, authorities say.

Police intervened at 10 p.m. local time. The 11-year-old was found dead and her father sustained a life-threatening head injury, while her mother was also injured but is not in critical condition, Halley said.

An hour later the Dutch man and his wife surrendered and were taken into custody.

French authorities are investigating the attack. - Sophie PréVost/Maxppp/ZUMA

“We thought they were playing with firecrackers,” Yannick, a neighbor who heard the gunfire, told CNN affiliate BFMTV.

“The youngest girl came running to the neighbors shouting: ‘My sister is dead, my sister is dead,’” Yannick said.

Halley said Sunday “the motives for the tragedy are not yet known.” But, according to the initial investigation, “it appears there had been a dispute between the two neighbors for several years over a piece of land adjoining the two properties.”

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

Marguerite Bleuzen, the mayor of Plonévez-du-Faou, a town bordering Saint-Herbot, told BFMTV Sunday she had been made aware of a dispute between neighbors several years ago.

“I intervened with my deputies when we were elected. There was a problem with the land, noise complaints,” Bleuzen said.

“I’m dumbfounded,” the mayor added.