NOUAKCHOTT, Mauritania (AP) — Mauritanians are going to the polls to elect a new president.

The outgoing leader's preferred successor on Saturday faces five opposition candidates in this West African nation threatened by Islamic extremism.

One candidate of sub-Saharan African descent wants to improve race relations in a country where activists estimate tens of thousands of people still live in slavery despite the practice being banned for decades.

Mauritania has suffered five coups since independence from France in 1960, and has been led by military rulers for much of that time.

President Mohamed Ould Abdel Aziz seized power in 2008 and is barred by the constitution from seeking another term. In respecting term limits instead of seeking to change the constitution he contrasts with several leaders elsewhere in Africa in recent years.