Initial results from a presidential poll in DR Congo began to trickle in on Friday after shambolic elections spread over several days which the authorities deemed successful.

The central African nation's electoral commission, Ceni, announced results for Congolese voters living in South Africa, Belgium, France, Canada and the United States.

The results represent a minuscule proportion of the overall votes cast, but they indicated a provisional lead for incumbent President Felix Tshisekedi, who is running for a second term.

Poor but mineral-rich Democratic Republic of Congo held four concurrent polls on Wednesday to elect the president, lawmakers for national and provincial assemblies as well as local councillors.

Massive delays and bureaucratic chaos marred the vote and some polling booths were unable to open at all.

Ceni extended voting in some areas until Thursday.

In a statement, the electoral commission said that no polling station was authorised to open on Friday.

However, voting continued in some places on Friday, according to officials, especially in the more remote areas of the vast country the size of western Europe.

People were casting votes in Kilembwe, in the Fizi territory of South Kivu province, in the east, for example, after voting materials only arrived late on Thursday.

"Everything should be finished by (the afternoon) at the latest," the territory's administrator Sammy Kalonji told AFP.

Didi Manara, from the Ceni, said that "at least 97 percent" of the roughly 75,000 polling stations in the DRC had been able to open.

Given the size of the country, he said, this represented a "miracle". DR Congo is roughly the size of continental western Europe.

In a preliminary statement on Friday, the Carter Center -- which observed the elections -- said there had been "serious irregularities" at 21 out of 109 polling stations it visited. The ballot had proceeded "relatively well" in the other 88.

In 24 polling stations, its observers identified technical problems with electronic voting devices, the US-based group added.

- Tensions feared -

 

While the Congolese government acknowledged delays late on Wednesday, it hailed the efforts of voters and the electoral commission.

Results from the presidential election in the Congolese diaspora were published on Friday night.

Ceni is set to start announcing provisional results for the DRC's 26 provinces on Saturday.

Around 44 million Congolese in the nation of 100 million were registered to vote, and more than 100,000 candidates were running for various positions.

Tshisekedi, 60, is considered the front-runner in the first-past-the-vote presidential vote, especially given that he is facing a divided opposition.

The main opposition candidates are gynaecologist Denis Mukwege, 68, the 2018 Nobel Peace Prize laureate; 58-year-old business magnate and former provincial governor Moise Katumbi; and 67-year-old ex-oil executive Martin Fayulu.

They have all criticised the election's disarray, and warned against the potential for electoral fraud.

There are fears that tensions will spike when the results are announced.

The DRC is a turbulent country with a long history of authoritarian rule and conflict.

On Thursday, the United States repeated a call for transparent and fair elections in the country.

"We will not hesitate to call out irregularities," said a US State Department spokesman.