NOUAKCHOTT: The army general who led a military coup that toppled Mauritania's first elected head of state last August was on Sunday declared the winner of a presidential election organised by his junta.

Mohammed Ould Abdel Aziz, who resigned his commission to stand, won 52.58 of ballots cast in the first round of voting on a turnout of 64.58 percent, according to provisional results released by his interior minister, Mohamed Ould Rzeizim.

During a press conference awaiting validation of results by authorities managed by the government installed after the coup, Ould Abdel Aziz dismissed opposition claims of a voting "charade."

"Whatever (they) say, our camp did not engage in fraud," he said. "It's not enough just to say there has been fraud -- you have to provide proof.

"That is now a matter for the constitutional council and the interior minister -- the law is very clear on that point."

He promised to fight against disease while raising educational levels and building the sem-desert north African country's infrastructure.

Ould Abdel Aziz also said he would beef up his army "to fight terrorism in all its forms" after an American teacher was shot dead in the capital Nouakchott last month, with an Al-Qaeda offshoot claiming responsibility.

"We will fight terrorism in all its forms... by strenthening the resources at the army's disposal," he vowed.

Ould Rzeizim said earlier that there was no information that would lead him to call the conduct of the vote into question, following a statement issued by opposition candidates contesting initial results.

Four candidates for the presidency, including the speaker of parliament Messaoud Ould Boulkheir, denounced what they called "prefabricated results" at a joint press conference Sunday.

After polling stations closed late Saturday, Ould Abdel Aziz's supporters had already taken to the streets to celebrate.

Ould Abdel Aziz was the leader of the coup last August that ousted Sidi Ould Cheikh Abdallahi, but he officially stepped down as head of the junta in April and resigned from the army to contest Saturday's election.

At the joint opposition press conference, Messaoud Ould Boulkheir told reporters: "The results which are starting to come out show that it is an electoral charade which is trying to legitimise the coup."

Ould Boulkheir, leading an anti-coup front, was Ould Abdel Aziz's nearest challenger with 16.29 percent of votes.

With him at the press conference was Ahmed Ould Daddah, head of the main opposition party, who came in third with 13.66 percent.

Also present were Ould Mohamed Vall, the junta chief in 2005-2007, who scored 3.81 percent; and Hamai Ould Meimou, an independent candidate.

Their combined declaration called on the international community to carry out an independent enquiry into voting irregularities.

They also called on "competent bodies" not to validate the results, and for the Mauritanian people to "mobilise to defeat this electoral coup d'etat."

More than 300 international observers attended the vote, from the African Union, the International Organisation of French-speaking Countries (OIF) and the Arab League.

But there were no observers from Europe, officially for scheduling reasons, said one diplomatic source.

In April the European Union suspended its cooperation with Mauritania because of the coup, also freezing 40 million euros (56.5 million dollars) in aid.

Brussels said cooperation would only resume once there had been a "return to constitutional order."

Saturday's election was meant to restore democracy in Mauritania, which has mostly known military rule since independence in 1960, by restoring constitutional democracy to this arid, but potentially oil-rich country.

Some 1.2 million of the nation's three million people were eligible to vote.