The Louisiana home where a nine-year-old boy playing with a gun in a bedroom closet accidentally shot dead his younger brother.

The boys’ mother faces a child desertion charge, authorities said.

Colonel John Fortunato, a spokesman for the Jefferson Parish Sheriff’s Office, said 29-year-old Generra Brown was issued a court summons for the misdemeanour charge because she left the children unsupervised at a Marrero home before the Tuesday evening shooting that killed her son, Melvin Brady.

Fortunato said investigators believe that Brown, a home health care professional, was caring for a neighbour across the street when her nine-year-old son found a loaded gun while he and his brother were playing in a bedroom closet.

As the older brother handled the handgun, it fired one shot that struck the younger child.

The five-year-old was pronounced dead at the scene.

Outside the tragic scene. The boy is the fifth child to die in an accidental shooting in metro New Orleans, say local media.Source:Supplied

Officers responded to the shooting around 6.30pm on Tuesday.

Brown dialled 911 after learning about the shooting from the older child.

Melvin’s death marked the third time a child has died in metro New Orleans in an accidental shooting this year, New Orleans media reports.

He also was the 14th person to die in accidental shootings in Louisiana in the same period.