Conditions were ripe for an incident, as the 23,000-capacity stadium held a crowd that day of approximately 30,000. To make matters worse, officals did not segregate supporters of the fierce derby rivals, so that they were all intermingled in the packed stadium. All that was needed was a spark, which was provided when Chiefs scored a controversial goal.
The Pirates supporters erupted, reportedly throwing objects, including cans and fruit, at the Chiefs supporters. A number of fights broke out and, according to some accounts, there were knife attacks. The deaths, however, were caused by the ensuing stampede as supporters rushed to get out of the stadium, with people getting trampled or crushed against the fences.
The same two teams were involved in a similar incident on 11 April 2001 at Johannesburg's Ellis Park Stadium. That time, 43 people died, surpassing the previous incident as the country's worst stadium tragedy.