Mamadou Tandja, the president of the vast desert nation of Niger, has secured an additional three years in office and unlimited runs at future terms in a referendum that opposition officials have called a coup d'etat in all but name.

Mr. Tandja, a 71-year-old former army colonel who had promised to step down after the second of his two terms expired in December, thanked voters even before the official results were announced Friday by the country’s electoral commission...

... Mr. Tandja's move to extend his tenure, condemned by the United States and the European Union, was seen as another setback for democracy in the region and the nation, which had taken halting steps toward political openness after a post-colonial history of military coups.