The plight of Botswana's Gana and Gwi hunter gatherers, who are fighting their removal from the Central Kalahari Game Reserve, received a publicity boost on the fringes of an international mining conference in Canada on Monday.
About 700 people, also known as the Basarwa, are contesting their removal from the reserve - which they consider their ancestral land and burial grounds - to resettlement camps. They also want their hunting rights back.
The Botswana government says it can no longer afford to provide the infrastructure they need to live in the park and want them all removed to the camps.
A recent court challenge against their removal was dismissed on a technicality and they are currently trying to raise money to return to court.
Lobby group Survival International, which helps raise awareness of threatened peoples, placed an advertisement about them in Canada's Toronto Star to co-incide with the opening of the Global Mining, Minerals and Sustainable Development Conference there.
Survival International chose the conference because they believe the real reason the Basarwa are being removed is because a vast pocket of diamonds has been discovered in the park. Representatives of Botswana's diamond industry were expected to attend the conference.
"De Beers downplays it but they spent tens of millions on feasibility studies and one of the most important finds was in the Kalahari in recent years," said Survival International director Stephen Corry.
He said the removal of the Bushmen was also in violation of an International Labour Organisation convention on tribal lands. "This law specifically says that tribal people have ownership rights on the land they use."
Botswana has not ratified the convention.
Survival International is also to hold vigils throughout Europe including London, Madrid, Paris and Rome.
Meanwhile, Maureen Akena of rights group Ditshwanelo, who are instructing the lawyers in the court challenge, said: "Financial considerations are of significance in this matter as the decision [to return to court] will hinge on the ability of the negotiating team to raise funds."
One of the lawyers Glyn Williams told IRIN recently that between US $15,100 to US $30,200 was needed to launch a fresh court action.
Meanwhile, less than 100 people remain in the reserve, refusing to move even though their basic services have been cut off and their hunting licences taken away.