WARNING: This video contains footage which some viewers may find distressing

Two white South Africans who were filmed forcing a wailing black man into a coffin were found guilty on Friday of kidnap, assault and attempted murder.

The men said they had caught Victor Mlotshwa trespassing on their farm in possession of stolen copper cables. The 20-second video, widely circulated on social media last year, shows Mlotshwa cowering inside a coffin as one man pushes the lid down and the other threatens to put petrol and a snake inside.

The case, heard at a court in Middelburg, about 160 km (100 miles) east of the capital Pretoria, has caused outrage in a country where deep racial divides persist 23 years after the fall of apartheid.

The accused, Theo Jackson and Willem Oosthuizen, have yet to be sentenced and have the right to appeal.

Black people make up 80 percent of South Africa's 54 million population yet most its wealth remains in the hands of white people who account for about 8 percent of the population.