JUBA, South Sudan — The South Sudanese opposition leader Riek Machar has fled to the Democratic Republic of Congo after being targeted by government troops, his spokesmen said on Thursday, as a fragile peace deal to end more than two years of civil war unravels in the world’s youngest country.
In accordance with the 2015 peace deal, which received international backing, Mr. Machar returned to Juba, the capital, in April to resume his post as deputy to his rival, President Salva Kiir. But clashes between factions loyal to the men erupted months later. Mr. Machar’s residence was destroyed, and he and his troops were driven from the capital.
“He was being pursued constantly since he withdrew from Juba,” said an opposition spokesman, Mabior Garang de Mabior, adding that Mr. Machar would soon travel to the Ethiopian capital, Addis Ababa.
Peter Biar Ajak, a co-director for South Sudan at the International Growth Center, said Mr. Machar had no choice but to flee before his forces were decimated.
“Aside from avoiding capture, getting out of the country was the only way he could attempt to rebuild support within his constituency and remind the international community that he is still relevant to the peace process,” Mr. Ajak said from Cambridge, England.
A spokesman for the United Nations added a layer of intrigue on Thursday, asserting that the organization’s peacekeeping mission in the Democratic Republic of Congo, known by its acronym Monusco, had assisted Mr. Machar, his wife and 10 others in safe travel once they had crossed into the country from South Sudan, which happened on Wednesday. The spokesman, Farhan Haq, also hinted that Mr. Machar had received medical attention from Monusco.
Mr. Haq told a regular briefing at the United Nations headquarters in New York that Mr. Machar was now at an unspecified location in the Democratic Republic of Congo, but declined to elaborate on why Mr. Machar had needed medical attention.
“We took him from one part of the D.R.C. to another,” Mr. Haq said. “Right now he’s in the hands of the authorities of the D.R.C.”
Tens of thousands of people died in a civil war that began in December 2013 and pitted troops loyal to Mr. Machar, a former vice president, against the forces of Mr. Kiir. Both sides are accused of committing atrocities against civilians.
Supporters of Mr. Machar cried foul when Mr. Kiir accepted the nomination last month of a new vice president, the former mining minister Taban Deng Gai, to replace Mr. Machar in the transitional government.
Mr. Kiir’s spokesman, Ateny Wek Ateny, said that Mr. Machar’s departure would have no effect on the peace process.
“He has not been in Juba for a long time,” he said. “So what difference would it make if he surfaces in another country?”
Many of Mr. Machar’s supporters have been sheltering in United Nations displacement camps since the war broke out, when members of Mr. Machar’s ethnic group, the Nuer, were targeted for attacks in the capital city.
Since the latest fighting, last month, the camps have grappled with food shortages, overcrowding and a series of brutal rapes just beyond their walls that are thought to have been mostly perpetrated by government soldiers.
A Nuer schoolteacher inside the camp, Yuanes Geng, 34, said he and his friends were not yet worried about Mr. Machar’s departure.
“If he has left the country, it’s O.K., as long as he has left with a diplomatic mission in mind,” Mr. Geng said. “If he doesn’t come back, that would be a problem. But I think he will come back very soon.”