A suspect was in custody and police called the shooting an isolated incident.

The family was headed home from a city-sponsored event downtown when they decided to stop at a few homes, Sumter Police Chief Patty Patterson said. The father and his four children approached a home with a porch light on about 8.30 pm while their mother waited nearby in a vehicle.

As the family was at the door, they thought they heard fireworks.

The 12-year-old boy, his father and brother were all hit by the gunfire. The boy died at a hospital, Coroner Verna Moore said. The other two children were not hurt.

The boy's father and brother were taken to a hospital with non-life-threatening injuries. Chief Patterson has not released the man's name or the identities of the family.

She also would not release any more details about the shooting.

The police said there were other people inside the home at the time of the shooting, but she didn't expect any of them to be charged.

A neighbour said he heard a loud noise about the time of the shooting and thought it was simply Halloween mischief.

'I thought, trick-or-treat night - pranks go down. Anything goes,' said Mr Lenwood Dixon, 49. 'I heard a noise like maybe gunfire, then my daughter saw a bunch of lights flashing and saw some cops.'

'I'm surprised. Since I was here, I'd never heard of anything like that happening. It's a quiet neighbourhood,' he said. 'You don't see many children in the neighborhood. It's more elderly.' -- AP