French prosecutors have opened a preliminary investigation into new allegations of sexual abuse against French troops based in Central African Republic, a judiciary source said on Tuesday.

The prosecutors' office said the probe was opened after the U.N. passed on allegations of sexual abuse involving French troops that took place in the eastern town of Dekoa between 2013 and 2015.

The scandal-tainted U.N. peacekeeping mission in the Central African Republic said Friday that fresh allegations of sex abuse by its soldiers had surfaced in the center of the country.

The accusations are the latest to hit the MINUSCA force in the deeply poor and restive country, where both U.N. and French peacekeepers have been accused of widespread abuse and offering food to children in return for sex.

A rebel group in the Central African Republic has captured and handed over to U.S. forces a commander of the infamous Lord's Resistance Army (LRA), one of its leaders said Monday.

"Our forces captured the commander 'Sam' at the weekend at Mbangana in the north east," Mahamat Dea, a leader of the Popular Front for the Renaissance of Central Africa (FPRC), told AFP.

The final round of presidential elections in the Central African Republic, which had been scheduled for Sunday, has been postponed over organizational problems, the electoral authority said Wednesday.

"We can't hold the election on Sunday, it's impossible, we will soon announce a new date," said Julius Ngouade Baba, a senior official at the electoral authority (ANE).

U.N. peacekeepers are facing fresh allegations that they sexually abused four young girls in the Central African Republic, the latest in a wave of child rape cases to hit the mission.

The United Nations said Tuesday it had informed three countries of the claims and asked them to investigate their soldiers serving in the MINUSCA mission in Bangui.

Voters went to the polls in Central African Republic to elect a president and parliament in crucial elections seen as vital to restore stability after years of sectarian bloodshed.

Snaking queues had formed outside polling stations in the capital Bangui by the scheduled start of the election at 0600 GMT but in many places the start of voting was delayed for a few hours by logistical glitches.

Campaigning kicked off in earnest on Tuesday in the Central African Republic, where no fewer than 30 candidates are running for president.

The long-delayed presidential and parliamentary polls set for Sunday are aimed at ending more than two years of sectarian conflict.

Two people were killed Sunday as heavy weapons fire and clashes in the Muslim district of Bangui, the Central African Republic capital, marred a key constitutional referendum aimed at ending years of sectarian strife.

An AFP journalist saw the bodies of two people lying in a mosque in Bangui's PK5 Muslim district, while a hospital source said 20 others were wounded there, in clashes pitting supporters against opponents of the referendum seen as key to a return of normalcy in the divided nation. 

An ex-Seleka rebel leader said Friday he would not allow elections due later this month to take place in the regions of the Central African Republic under his control.

The country is preparing to hold a referendum on December 13 on a proposed new constitution ahead of nationwide polls on December 27, following years of violence after a bloody coup in 2013.

No money, no food, no petrol. But there is fear. Plenty of it.

It is fear that haunts the dusty streets of PK5, a Muslim neighborhood in Bangui, the Central African Republic (CAR) capital that Pope Francis plans to visit on Sunday and Monday.