(Fixes typo in first paragraph)

By Ange Kasongo and Djaffar Al Katanty

KINSHASA/GOMA, Democratic Republic of Congo (Reuters) -Democratic Republic of Congo was holding presidential and legislative elections on Wednesday after a chaotic campaign marred by opposition allegations of fraud, electoral violence, and logistical setbacks that could prevent many from voting.

At stake is not just the legitimacy of the next administration. Congolese election disputes often spark violent unrest with potentially far-reaching consequences. Congo is the world’s third largest producer, and the top producer of cobalt, a battery component needed for the green transition.

Delays were reported in several towns in Congo’s rebel-plagued east and in the capital Kinshasa, voting materials had not arrived at polling stations and voter lists were not published.

“It is total chaos,” said presidential candidate Martin Fayulu, runner-up in the disputed 2018 presidential election.

Fayulu said that while the vote was well-organised in the upmarket Gombe district in the capital where he voted, it was not the case elsewhere.

“If all the people don’t vote in all the polling stations indicated by the CENI (election commission), we won’t accept these elections,” Fayulu warned.

Another presidential candidate, Nobel Peace Laureate Denis Mukwege, told journalists after voting that he was concerned about how election day was progressing. Before the vote he warned that the “electoral fraud of the century (is) taking place”.

Meanwhile millionaire businessman and former governor Moise Katumbi, a strong challenger in the presidential race, urged his supporters to monitor the publication of results in each polling station.

“The only results that we will accept are results that must be posted at each polling station. For now I’ll not judge the organisation of the vote but there are many failures,” he said after voting in the mining town of Lubumbashi.

In the eastern cities of Goma and Beni, some people struggled to find their names on voter lists, which were only made available at their polling stations on Wednesday morning, according to Reuters witnesses.

In Bunia, also in eastern Congo, security forces fired warning shots to disperse protesters after a voting centre was vandalised and kits destroyed, a Reuters reporter said.

A provincial election commission official told journalists that people displaced by violence in the region had protested because they could not get back to their home towns to vote.

ELECTORAL TRANSPARENCY

For months, Congo’s national election commission has insisted it could deliver a free and fair vote as promised across Africa’s second-largest country, even as independent observers and critics flagged irregularities they said would jeopardise the legitimacy of the results.

About 44 million Congolese are registered to take part in the election, which also includes regional ballots.

As voting day neared, the authorities sought extra helicopters, raising concerns about the commission’s ability to open polling stations in areas otherwise unreachable due to bad roads or a lack of security.

Even so, before election day, the CENI said it would not be able to organise voting in two territories in the rebel-torn eastern province of North Kivu and one territory near Kinshasa due to security threats.

Full provisional results are expected by Dec. 31.

President Felix Tshisekedi is competing against 18 opposition challengers in the hope of a second term running the mineral-rich yet poverty-stricken nation.

Opposition candidates have wooed voters with pledges to bring stability, peace, and the economic development they say was absent from Tshisekedi’s first term.

They and religious and civil society electoral observers have sounded the alarm about transparency, highlighting issues including the voter list and illegible ID cards.

The election commission has repeatedly rejected the opposition’s allegations of fraud.

The election will be decided in a single round, requiring a simple majority of the vote to win. The final run-up to the vote has been particularly fraught.

Two parliamentary candidates were killed in separate incidents on Dec. 15 – part of a spate of election-related violence condemned by human rights groups and the European Union.

Ahead of election day in Kinshasa, some locals were not convinced their vote would count. “Every time we vote, we are disappointed, but if I had to vote, it would be for a change,” said 43-year-old Lucie Mpiana, who is unemployed.

Polls are due to close at 1600 GMT.