Police were defending themselves when they fired into a crowd of protesters and killed two residents in Relela, South Africa, a spokesman said. Police spokesperson Hangwani Mulaudzi said officers was reacting to attacks by residents -- angered over the fatal shooting of a 15-year-old boy and the death of a 20-year-old woman last week -- who marched on the police station and threw stones at officers Tuesday, EyeWitnessNews.com reported Wednesday. "The members saw their lives were in danger," Mulaudzi said. "We believe this was actually a plot to kill them. We had to engage the crowd and unfortunately two people lost their lives." Officials estimated up to 2,000 protesters were at the police station and at least 15 officers were injured in the confrontation. Nineteen police vehicles were damaged and nine protesters were arrested. The South African Broadcasting Corp. said at least eight people have been killed in clashes between protesters and police during the last two weeks.