Earlier news reports indicated that between four and seven people were arrested following threats by Afrikaner nationalist groups against the Mangaung conference, but police have since denied such a link.
The City Press reported on Sunday night that the group of people were arrested after investigations showed they were planning an attack on one of the main marquees at the ANC's national electoral conference.
It appears that no one has appeared in court following the arrests. All police communications on the issue are being handled by Free State police spokesperson Brigadier Billy Jones, who could not be contacted on Monday.
But Jones told the South African Press Association (Sapa) that police were not "at this stage linking the arrests with the conference at all".
Francois Cloete, national secretary of the newly formed political party, the Federal Freedom Party (Federale Vryheidsparty or FVP) confirmed to the Mail & Guardian on Monday that "two of the party's management were arrested by the ANC government for high treason".
One of them was the party's president, whom the M&G has identified from the party's website as Hein Boonzaaier, while the other was a member of its executive council, whom Cloete did not name.
Both were arrested near Naboomspruit in Limpopo on Sunday, he said.
Sapa had earlier quoted ANC spokesperson Keith Khoza as saying that "preliminary information suggested the men were planning to bomb the marquee where [Jacob] Zuma and 4 500 delegates" were holding their conference.
The brigadier was quoted as saying that the suspects are between the ages of 40 and 50 and that crime intelligence and the Hawks had searched their premises and seized evidence.
An intelligence source told the M&G that both crime intelligence and counter-intelligence were involved in the operation, which saw the group of suspects arrested in separate operations on Sunday in Limpopo, the Free State and the Northern Cape.
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In an email to the M&G Cloete claimed that the two arrested men had been denied access to their legal teams.
"There are also rumours circulating that the government seeks to create a second Boeremag case to once again impose fear in [the minds of] the conservative whites, while their rights are already being trampled on a daily basis," he wrote.
"This is just another clear sign to try and derail freedom-seekers to obtain self-determination."
A National Prosecuting Authority source told the M&G that the case docket has not yet been handed over to the NPA and that the investigation is still at an early stage.
The FVP was formed in October after it registered with the Independent Electoral Commission as a political party.
Cloete said that it was established to promote "self-determination of the Afrikaner/Boer people in a confederal political model".
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