Gen Abdelaziz ousted Mauritania's only democratically elected leader
Mauritania's military leader, Gen Mohamed Ould Abdelaziz, has been declared the winner of the country's presidential election.
The interior minister announced he had won outright, with 52% of the vote in Saturday's poll.
Gen Abdelaziz seized power in a coup last year.
Even before the results were announced, his challengers said the outcome had been "prefabricated" and called for an international inquiry.
Dominated by light-skinned Arabic-speakers (Moors)
Slavery still practised, campaigners say
Black Africans complain of discrimination
Mostly in the Sahara Desert
Earlier, one of the main opposition candidates, Messaoud Ould Boulkheir, told a news conference: "The results which are starting to come out show that it is an electoral charade which is trying to legitimise the coup."
A statement from the group of four challengers read: "We firmly reject these prefabricated results, secondly we call on the international community to put in place an inquiry to shed some light on the electoral process."
There were nine candidates in all.
Voter turnout was 61%, the election commission said.
The military coup of August 2008 ousted Mauritania's only democratically elected leader since independence in 1960, Sidi Ould Cheikh Abdallahi.
He had been in power for less than a year and a half.