Guinea's junta chief, Gen Mamady Doumbouya, has won the presidential election by a landslide, getting 86.7% of the vote, according to provisional results published by the election commission.

The general is hoping to legitimise his rule after seizing power in a coup in 2021.

A civil society group calling for the return of civilian rule has condemned the election as a "charade" after Gen Doumbouya's main rivals were barred from contesting, while opposition candidates said irregularities marred the poll.

The Democratic Front of Guinea's flagbearer, Abdoulaye Yero Balde, came a distant second with 6.6%, followed by the Liberal Bloc's Faya Lansana Millimono with 2%, provisional results show.

On Monday, internet monitoring group NetBlocks reported that access to social media platforms TikTok, YouTube and Facebook had been restricted as Guineans waited for the full results.

There has been no official comment on the restrictions, but opponents see it as an attempt by the junta to stifle criticism of the results.

The 41-year-old general's victory gives him a seven-year mandate. Should the results be challenged, the Supreme Court has eight days to validate them.

Millimono said on Monday that the election was marred by "systematic fraudulent practices", citing the expulsion of poll observers, ballot stuffing and intimidation.

The ruling party and the government have yet to comment on the complaints.

After overthrowing then-83-year-old President Alpha Condé in 2021, Gen Doumbouya promised not to seek election and to hand power to a civilian.

"Neither I nor any member of this transition will be a candidate for anything... As soldiers, we value our word very much," he said at the time.

The junta leader broke his promise by putting his name on the ballot after a new constitution, implemented in September, permitted him to run for office.

Djenabou Toure, the country's top election official, who announced the provisional results, put the voter turnout at more than 80%.

However, a civil society group, the National Front for the Defence of the Constitution, said in a statement on Monday that the turnout was low.

"A huge majority of Guineans chose to boycott the electoral charade," the National Front for the Defence of the Constitution was quoted as saying by the AFP news agency.

Eight other candidates took part in Sunday's election, but with the exclusion of the main opposition parties RPG Arc en Ciel and UFDG, none of the participants has a solid political footing.

According to the provisional results, six of them got less than 2% of the vote, with Mohamed Nabe getting 0.8%.

Although he is popular with many of Guinea's youth, Gen Doumbouya has been criticised for restricting opposition activities, banning protests and stifling press freedom in the run-up to the elections.

The general justified deposing Condé on similar charges - including rampant corruption, disregard for human rights and economic mismanagement.

Guinea has the world's largest bauxite reserves and some of its richest iron ore. Last month, authorities launched the gigantic Simandou iron-ore mine to widespread anticipation.

However, over half of the population lives in poverty, according to World Bank figures.