Kinshasa, Dec 30 (AFP) After two years of delays, crackdowns and political turmoil, the Democratic Republic of Congo voted Sunday in presidential elections that will determine the future of Africa's notoriously unstable giant.

Facing fears of bloodshed and a test of integrity, polling day appeared to be free from violence but frustration over problems and controversial voting machines ran deep.

The vote gives the DRC the chance of its first peaceful transfer of power since it gained independence from Belgium in 1960.

Analysts, though, say the threat of upheaval is great, given organisational hitches and suspicion of President Joseph Kabila, who refused to quit in 2016 after his two-term limit expired.

The election's credibility has been strained by repeated delays, fears of chaos on polling day and accusations that electronic voting machines would help to rig the result.

On election eve, talks aimed at averting violence after the vote broke down. Opposition frontrunners Martin Fayulu and Felix Tshisekedi refused to sign a proposed code of conduct with Kabila's preferred successor, Emmanuel Ramazani Shadary. They accused officials with the Independent National Election Commission (CENI) of thwarting changes to the text.

The UN, US and Europe have appealed for the elections to be free, fair and peaceful -- a call echoed by the presidents of Angola, Botswana, Namibia, Zambia and the neighbouring Republic of Congo.

And in the Vatican, Pope Francis led thousands of worshippers in St. Peter's Square on Sunday in prayers for "normal and peaceful" elections.

Candidates posed for the cameras as they went to cast their ballot. "You saw how I campaigned, everything that happened. I'll be elected, I'll be president from tonight." Shadary told Actualite.cd news site, adding: "People must vote. We have to avoid violence." Meanwhile Tshisekedi predicted: "Victory is ours."

Many voters said they were exhilarated at taking part in the first elections after the nearly 18-year Kabila era.

"I feel liberated, freed," said Victor Balibwa, a 53-year-old civil servant, casting his ballot in Lubumbashi, the country's mining capital in the southeast. But there was also much evidence of organisational problems, including with the contested voting machines.

In some places, long queues built up because of a lack of electoral roll, technical problems or because voters could not find their names on the lists, AFP reporters found.

At Imara in Lubumbashi, 30-year-old voter Diane Mumba, said, "The machines have been breaking down again and again for the last two hours. I don't know when I am going to vote." An election observer in Lubumbashi confirmed, "there are five or six polling stations where the machines aren't working. You have to wait for a technician".

In Kinshasa, an elderly lady said she had trouble with the touch-screen voting.

"It's very complicated. I pressed the button without really knowing who I voted for -- I didn't see my candidate's number or face," she complained.

In the eastern city of Goma, voters who began queueing before the cut-off of 5pm were allowed to stay on to cast ballots. In the Kinshasa district of St Raphael, where a delay in voting sparked anger earlier, ballotting was being allowed until 10 pm, an African Union observer told AFP.

Twenty-one candidates are running in the presidential election, taking place alongside legislative and municipal polls.

The frontrunners include Kabila's champion Shadary, a hardline former interior minister facing EU sanctions for a crackdown on protesters.

His biggest rivals are Fayulu, until recently a little-known legislator and former oil executive, and Tshisekedi, head of a veteran opposition party, the UDPS.

If the elections are "free and fair," an opposition candidate will almost certainly win, said Jason Stearns of the Congo Research Group, based at the Centre on International Cooperation at New York University.

Opinion polls make Fayulu clear favourite, garnering around 44 per cent of voting intentions, followed by 24 per cent for Tshisekedi and 18 per cent for Shadary, he said.

However, "the potential for violence is extremely high," he warned. Roughly half of respondents said they would reject the result if Shadary was declared winner, and would distrust DRC courts to settle a dispute fairly.

Almost the size of continental western Europe, the DRC is rich in gold, uranium, copper, cobalt and other minerals, but little wealth trickles down to the poor.

In the last 22 years, it has twice been a battleground for wars drawing in armies from central and southern Africa.

That legacy endures in the jungles of eastern DRC, where militias have carried out hundreds of killings.

Insecurity and an ongoing Ebola epidemic in part of North Kivu province, and communal violence in Yumbi, in the southwest, prompted the authorities to postpone the elections there until March.

Around 1.25 million people in a national electoral roll of around 40 million voters are affected.

Despite this, the elections in the rest of the country have gone ahead. The provisional results will be announced on January 6, final results on January 15 and the new president sworn in on January 18. (AFP) SCY

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