Carel Johannes "Kallie" Delport was born in 1956 in South Africa. As a child, he suffered from meningitis, which may have contributed to his later mental health issues. He was declared unfit for military service for unspecified reasons. Delport worked on his father Marthiens' farm in Allerkraal, near Ladysmith, KwaZulu-Natal, earning R300 a month. He had a history of mental illness and was twice charged with and acquitted of manslaughter after shooting two alleged cattle thieves. Despite his family's concerns, his father allowed him to own firearms; at the time of the massacre, Delport legally possessed 13 firearms and was known locally as an excellent marksman, often participating in wildlife culling. A psychiatric evaluation after his arrest revealed that Delport had an IQ of 78 and suffered from borderline personality disorder.

On January 20, 1992, following an argument with his father over the sale of three calves, Delport armed himself with a .357 Magnum revolver and shot his father, Marthiens Delport, in the chest on the veranda of their farmhouse. He then shot the housemaid, Makhozana Alzina Ntombela, in the kitchen. Delport set fire to his mattress and car, leading to the destruction of the farmhouse. Approximately 750 meters from the farm, he killed Msamaniso Mdladla and Petros Ndlala, two black men who had come to buy the calves. Delport then drove to Ladysmith, intending to set his stepmother's car on fire, but upon failing to find it, he began randomly shooting people in the street with a Ruger Mini-14 rifle. He killed five more individuals, including traffic officer Prithlal Rambally, and wounded 11 others. Delport then drove towards Newcastle, shooting at commuters in a bus and injuring six. He was eventually apprehended on a road outside Ladysmith after a brief chase and shootout with police, during which two officers were wounded. Police recovered the rifle, four 30-round magazines, the revolver, and over 3,600 rounds of ammunition from Delport's truck. Most victims were killed with precise shots to the heart.

During his trial, Delport pleaded not guilty, claiming he was of unsound mind and believed he was firing at "black shapes" attacking him. A psychiatric evaluation confirmed he was not mentally ill but had low intelligence and emotional instability. On October 21, 1992, Delport changed his plea to guilty and was convicted. On October 29, 1992, he was sentenced to a total of 39 years in prison: 22 years for nine counts of murder and 12 years for 21 counts of attempted murder, to be served concurrently. He was also declared unfit to ever obtain a firearms license.