South African President Jacob Zuma has called for calm after the killing of white supremist leader Eugene Terreblanche, saying it should not incite racial hatred.
Mr Terreblanche, 69, the far-right leader of the Afrikaner Resistance Movement, was attacked with pipes and machetes at his farm in the north-west of the country.
Two men, aged 21 and 15, have been arrested. AFP news agency quotes local police saying the men had argued with Mr Terreblanche over not having been paid for work done on his farm.
A statement from President Zuma's office said South Africans should not allow agent provocateurs to take advantage of this situation by inciting or fuelling racial hatred.
"No one is allowed to take the law into his own hands," the statement said, adding that "the killer or killers had no right to take Mr Terreblanche's life."
Mr Terreblanche's supporters violently opposed South Africa's all-race democracy and campaigned for a self-governing white state.
His party tried terrorist tactics and threatened civil war in the run-up to South Africa's democratic elections in 1994.