JOHANNESBURG—Four white men in South Africa face treason and terrorism charges over an alleged plot that included plans to attack the ongoing African National Congress political party convention and kill President Jacob Zuma and others, authorities said Tuesday.

The organizers called their plan "the Slaughter of Mangaung," using the ANC's name for its meeting in the central city also known as Bloemfontein, prosecutors said. They planned to use mortars and machine guns to kill leaders, possibly at a dining hall the men previously took photographs of at the University of the Free State, where the leadership meeting is being held, officials said.

The men were arrested in different locations across South Africa on Sunday, Brig. Billy Jones of the South African Police Service told The Associated Press on Tuesday. He confirmed the men were found with weapons, but declined to offer specifics.

"They found evidence supporting the investigation," Jones said. Investigators and prosecutors "are really protecting the investigation to ensure they get the conviction."

Police confirmed Monday they made the arrests, but at that time offered contradictory information about the men's plans and targets. On Tuesday, prosecutors identified those arrested as Mark Trollip, Johan Prinsloo, Martin Keevy and Hein Boonzaaier during a court hearing in Bloemfontein, the South African Press Association reported. Prosecutors said the men planned to create a new movement called the Boere Party, a word that means 'farmer' in Afrikaans, and is sometimes used to refer to whites.

Investigators have recorded phone conversations, emails and other material it collected from the men to show they plotted the attack, prosecutors said. One of those arrested was apprehended by police at a guesthouse in Bloemfontein, they said.

Some fringe groups support a return of racist apartheid rule in South Africa, a nation where white-dominated governments ruled for centuries before the country's first truly democratic elections in 1994. In July, a judge began handing down guilty verdicts in a long-running trial over the plans of a small, white extremist organization, called Boeremag, to launch a bombing campaign and assassinate then-President Nelson Mandela in the 1990s.

It is unclear how far along the planning was for this alleged attack or if the men posed a credible threat to the ANC and the nation's leaders. The ANC conference in Bloemfontein has been subject to tight security screenings since it began Sunday.

The ANC, which was once the main liberation movement challenging apartheid, has been the nation's governing party since the 1994 elections. President Zuma, 70, overwhelmingly won re-election as the ANC's president Tuesday after facing a challenge from his deputy Kgalema Motlanthe.


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