A South African father is facing manslaughter charges after allegedly shooting dead his teenage son, who he mistook for a criminal.

According to South African police, the accused, who had a firearm on him at the time, fell asleep in the car while waiting for his son outside his school.

The 14-year-old, who had been taking part in an evening study group, then knocked on the passenger window of his father's vehicle, Captain Mpande Khoza said.

“The father got scared by the knocking; he pulled out his firearm and shot in the direction of the person who was knocking,” he added.

The boy died on the way to hospital.

Pupils at the school in Ennerdale, south of Johannesburg, will receive trauma counselling, authorities say.

The shooting comes days after a nine-year-old girl was shot dead outside her school near Durban during a botched hijacking.

Her father is now being investigated for her accidental death, South African website TimesLive reports.