The United Nations has accused troops loyal to South Sudan's President Salva Kiir of carrying out atrocities including gang rapes and extrajudicial executions. Soldiers and security forces allegedly carried out the crimes in the latest upsurge of violence in the capital Juba in July.

More than 300 people, of which at least 73 civilians, were killed during fighting between government troops and rebels loyal to former vice-president Riek Machar.

"While some civilians were killed in crossfire between the fighting forces, others were reportedly summarily executed by Government (SPLA) soldiers, who appear to have specifically targeted people of Nuer origin," Zeid Ra'ad Al Hussein, UN High Commissioner for Human Rights, said in a statement.

He added that in at least two incidents, SPLA soldiers allegedly arrested eight Nuer civilians in in Juba's Munuki area and killed four of them in two nearby hotels.

The South Sudanese government has not responded to the allegations. However, the country's ambassador to the African Union James Pitia Morgan told the BBC the "UN has been making stories [up]". "Who has come forward to say that she has been raped?," he asked.

The UN comments came as Kiir fired six ministers believed to be allied to Machar, who was dismissed and replaced by Taban Deng Gai after fleeing Juba following the violence. The move came days after the minister of agriculture and food security, Lam Akol Ajawin, resigned claiming a peace deal signed in August 2015 had failed to be implemented.

Machar had fled South Sudan in 2013, when the country descended into civil war. His return earlier this year and his reinstatement as vice-president had restored hopes for the implementation of the peace process. However, tensions have been running high since his return.

Some analysts have pointed out that the replacement, which Machar deemed as illegal, could create fractures within the opposition with a group supporting Machar and the other supporting Gai. This, coupled with the recent resurgence of violence, is sparking fears that South Sudan could be plunged back into civil war.

South Sudan's descent into civil war

South Sudan's conflict erupted in 2013 when President Kiir, of the Dinka ethnic group, fired his deputy Machar, from the Nuer group, and his cabinet.

Ethnic-related violence then spread, with militia groups carrying out attacks in villages and areas known to be inhabited by either theDinka or Nuer tribes.

More than 10,000 civilians have so far been killed in the conflict, amid allegations of crimes against humanity committed by both sides, including extrajudicial killings, abductions, rape, torture and use of child soldiers. At least two million people have also been displaced.

Although the warring factions have signed at least seven peace deals, violence has continued, and a January report from the African Union blamed both leaders for the ongoing unrest.

Following the recent upsurge of violence, the South Sudanese government has been urged to accept more UN peacekeepers in the country, in a plan backed by the African Union (AU). However, the government opposed the plan, with the South Sudanese ambassador in the UK exclusively telling IBTimes UK the country does not want "to be meddled with by foreign troops."