The party that has ruled Angola continuously for nearly 50 years claimed victory on Friday in this week's election, after the electoral commission put its vote at 51% in a poll marred by low turnout and opposition accusations of fraud.

Fewer than half of Angola's registered voters turned out for Wednesday's election, which now looks certain to give President Joao Lourenco a second five-year term and extend the rule of the MPLA, which has governed the southern African oil producer since independence from Portugal in 1975.

With more than 97% of the vote counted, the election commission said on Thursday the formerly Marxist People's Movement for the Liberation of Angola, or MPLA, was ahead with a 51% majority while its longtime opponent, the National Union for the Total Independence of Angola, or UNITA, had 44.5%.

"We have reached yet another outright majority. We have a calm majority to govern without any kind of problem and we will do it," MPLA spokesman Rui Falcao told a news conference in the capital Luanda, a city that overwhelmingly voted for UNITA.

Wednesday's vote was Angola's most closely fought yet, with unprecedented gains for the opposition led by Costa Junior, who have complained about the counting process.

Analysts fear any dispute could ignite violence among a poor and frustrated youth who voted for Junior. The MPLA and UNITA, formerly both anti-colonial guerrilla groups, were on opposing sides of an on-off civil war after independence that lasted 27 years until 2002.

But since the election, the streets have been mostly calm, aside from the odd protest in favour of broken up by tear gas and baton-wielding police.

Civil society activists shared images on social media of dozens of young people marching, chanting and waving banners in protest against electoral fraud in the coastal town of Lobito on Friday. Reuters was unable to verify these images.

CLOSER THAN EVER

If the results tally stays as it is then UNITA, for the first time, will have deprived the MPLA of the two-thirds majority needed to pass major reforms - the ruling party will instead need the backing of other lawmakers.

But perhaps even more telling was how few voters showed up to choose between two political entities which have dominated Angolan politics since independence. Election data released on Friday showed that turnout was 45.65% of eligible voters.

Louren?o, 68, has pledged to extend reforms in his second term, including privatising poorly-run state assets. But many Angolans still live in poverty despite his promises of a fairer distribution of wealth in Africa's second biggest oil producer - a fact which benefited UNITA, popular with poor, jobless youths.

UNITA has challenged provisional results, saying its initial count of 40% of polling stations showed it only a whisker behind the MPLA. UNITA said this was a small enough margin for it to overhaul the MPLA once all ballots in Luanda were tabulated..

UNITA posted an image of Junior on its official Instagram account with the caption: "The President".

The MPLA posted a social media video of Louren?o thanking Angolans for the election outcome.

As she watched the news on her phone, 47-year-old Antonia Neto, who works at a coffee shop at Luanda airport, said she was not happy with the results but there was a glimpse of hope.

"There is a lot of discontent," she said. "Maybe things will be better in the next election."