After new evidence emerged implicating the South African army in the incident, the Truth and Reconciliation Commission announced in May they were opening a closed inquiry.

The crash, which happened just inside South African territory, killed more than 30 of Mozambique's senior government officials alongside their president.

At the time, 12 years ago, the South African government insisted that bad weather and pilot error caused Samora Machel's plane to hit a hillside.

Survivors questioned that conclusion, alleging that the plane had been shot down.

A South African inquiry ignored evidence at the time that the plane was diverted from its correct flight path by false radio signals.

Former members of South Africa's army and the intelligence service have been called to testify on Thursday.

Assassination suspicions

Samora Machel was one of the fiercest opponents of apartheid.

Before his death, he allowed the then outlawed African National Congress to launch guerrilla attacks from Mozambique against the South African government.

Members of the ANC who are now in the South African cabinet believe he was assassinated to put a stop to such support.

Samora Machel's widow, Graca, is now President Nelson Mandela's close companion, and he is said to have promised her that he will find out how her husband died.