Scorpions boss Bulelani Ngcuka, Minister of Justice Penuell Maduna and ANC veteran Mac Maharaj will all testify before the Hefer commission of inquiry, set up to establish whether Ngcuka and Maduna misused their offices due to "past obligations to apartheid".

Commission secretary John Bacon confirmed yesterday that Ngcuka and Maduna would be the last to take the stand before retired judge Joos Hefer in public hearings in Bloemfontein scheduled to start on Thursday.

Also included in the provisional line-up of confirmed witnesses are at least five journalists, including Ranjeni Munasamy, the former Sunday Times journalist who first wrote about the spying allegations, although her lawyers will argue that she cannot reveal her sources.

The judicial commission was set up two weeks ago to probe allegations that Ngcuka was an apartheid security police informer with the code-name RS452.

After Munasamy's article, which appeared in a rival paper, the City Press, former transport minister Mac Maharaj confirmed the allegations along with foreign affairs special adviser Mo Shaik, who is also set to testify this week.

Ngcuka, the national director of public prosecutions, has maintained his innocence in the face of the allegations, which surfaced in the wake of his comments that the Scorpions had found prima facie evidence of corruption against Deputy President Jacob Zuma, but had decided not to prosecute him because the case was "not winnable".

However, Shaik's brother, businessman Schabir, was charged.

Last week, the Hefer commission's terms of reference were broadened after a barrage of allegations against Maduna, under whose line management Ngcuka operates.

The allegations involved nepotism in his department, corruption and that he spied for the apartheid regime.

The commission will now probe whether the two men heading law enforcement in the country, misused their offices due to the alleged links with the apartheid-era government.

In an exclusive interview over the weekend with Independent Newspapers, Maduna also announced that he would not be available to serve in President Thabo Mbeki's cabinet after next year's election, as a result of the extreme pressure the ongoing allegations had put on his family and the ANC.

Bacon said the commission had also made contact with mining magnate Brett Kebble, who recently made various allegations against Maduna and Ngcuka, and yesterday also contacted Independent Democrats leader Patricia de Lille.

In 1997 De Lille told parliament Maduna's name and those of other ANC MPs of the time were on a list of apartheid-era spies.

Their appearance before the commission has not yet been confirmed.

First to appear on Thursday will be senior journalist Raymond Louw. He will make a voluntary public submission on behalf of the South African National Editors Forum's media freedom subcommittee.

Louw said he intended to argue on why a journalist should not give evidence before a commission.

Should the judge decide to go ahead, Louw will be followed by Munasamy, who has refused to testify, but has since been compelled to appear through the issuing of a subpoena.

She said yesterday her lawyer would petition Hefer on the reasons why she could not reveal her sources.

Bacon said other journalists asked to testify include Sunday Times editor Matata Tshedu, who refused to print Munasamy's article in which the spying allegations against Ngcuka were made.

Mona, the editor of City Press, which did run the article, and one of his journalists, Elias Maluleke, are also in the line-up of witnesses.

"We are still in the beginning phases our investigation," Bacon emphasised.

"We have made contact with the police service and security branches (to establish whether Ngcuka and Maduna were informers)."

Asked whether the commission had approached Zuma, who previously pledged to assist the commission, Bacon indicated that it was too early to determine whether his testimony would be be necessary.

No voluntary submissions had been received from the presidency.

With acknowledgements to Christelle Terreblanche and the Cape Times.