The Himba say that generations of graves would be flooded by the mooted 1 700-gigawatt hydroelectric dam, according to AFP. The Himba worry their ancestors will be angered and could react badly, causing havoc in their lives.

"We have not been consulted and we would lose our graveyards and sacred places, flooded by the dam," said a declaration signed by 26 Himba chiefs, released by local human rights campaigners NamRights.

"We will never give our consent to have our river blocked... our environment destroyed and our land taken away from us."

NamRights director Phil ya Nangoloh told reporters he had submitted the declaration to the Namibian government and to the AU Commission on Human and People's Rights.

The Himba argue the dam violates their rights under the UN Declaration on the Rights of Indigenous Peoples, which Namibia has voted in favor of in the United Nations General Assembly in 2007.

Chief Hikumine Kapika also invited UN Special Rapporteur on the rights of indigenous peoples, Professor James Anaya, to visit the affected Himba communities in Namibia.

In a sparsely populated country of two million people, about 18 000 Himbas live in north-western Namibia, with another 9 000 just across the border with Angola.

Their ancestors migrated from the Great Lakes region of central Africa about 200 years ago, and they have survived with their traditions despite wars and droughts.

Source: AFP