The 77-year-old President Denis Sassou Nguesso is aiming for re-election in the first round on Sunday in Congo-Brazzaville, where members of civil society have expressed "serious reservations" about the transparency of the election.

"One shot, K-O", proclaim the campaign posters of the candidate of the Congolese Labour Party (PCT) to mark his desire to be re-elected in the first round, as in 2016, against his six rivals.

The climate seems less heavy than five years ago. A few days ago, Frédéric Bintsamou said that the election "must not be an opportunity to reawaken the old demons of division".

The 56-year-old, better known as Pastor Ntumi, took up arms in the Pool region (south) after the disputed re-election of President Sassou Nguesso in March 2016. Regular forces counter-attacked in a closed-door conflict that displaced 140,000 people, according to humanitarian sources.

The authorities announced a ceasefire just before Christmas 2017.

For Mariela, a high school student in Pointe-Noire, the economic capital, the calculation is quickly made today: "Even if there is hardship, there is no war like in other countries. It's better to stay with Sassou, who keeps the peace in the country, at least that's good.

The "galère" and economic questions haunt the minds of voters in this oil-rich country of five million inhabitants, which was expecting a 9% drop in its GDP with Covid-19.

Even before the health crisis, GDP per capita had plateaued at $2,279 in 2019, compared to $3,922 in 2012 during the oil boom, according to the World Bank.

Faced with the impasse of all-oil, Sassou Nguesso said he was putting youth and agricultural development at the heart of his campaign, calling it "shameful" that the country imports most of what it consumes.

"The president is in a way acknowledging his own failure," said activist Franck Nzila.

- "Renewing democracy" -

The two main rivals of the outgoing president are two former ministers who have gone into opposition, Guy-Brice Parfait Kolélas and Mathias Dzon.

Kolélas, who came second five years ago, has pledged to free the two 2016 candidates sentenced in 2018 to 20 years in prison for "undermining state security", General Jean-Marie Mokoko and André Okombi Salissa.

In Mr Kolélas's stronghold, the Pool region, a man sighs as he waits for hours for a goods train to travel 18km. "We want change. I am 51 years old. When (the president) came to power I was ten years old.

The bishops' conference has already expressed "serious reservations" about the transparency of the election. The Catholic Church, which has been refused accreditation for its observers, fears that the internet will be cut off on Sunday, as it was in 2016.

However, the bishops' conference wants to test an application for computers and smartphones which should allow the downloading of the minutes of all the polling stations to have a real-time idea of the truth of the ballot box - except in the event of an internet cut...

Other concerns: the authorities refused to accredit a journalist from Radio France Internationale (RFI), and a 77-year-old human rights activist was arrested a few days before the vote, for undermining state security.

As with every election in Central Africa, voices are calling out to France, the former colonial power and main donor.

"The Republic of Congo, like French diplomacy, must return to democracy," wrote a group of French and Congolese activists in an article published by Le Monde.

"We call on France to condemn the pre-election deterioration of the political and civic climate," the signatories added.

President Sassou Nguesso took power in 1979. He was defeated in the first multi-party elections in 1992 by Pascal Lissouba.

But this very rare example of peaceful alternation in Central Africa ended in 1997 when Sassou Nguesso returned to power after a civil war with Lissouba's forces. In 2015, he broke the constitutional lock that limited the number of presidential terms to two.

For years, the Congolese government has also been in the news because of a high-profile investigation in France. In 2017, people close to President Sassou Nguesso were indicted for "laundering of public funds" in the so-called "ill-gotten gains" affair, which also targets the ruling families in Gabon and Equatorial Guinea.