Gambella, Ethiopia and Malakal, South Sudan — "If things don't improve, I'll leave for Ethiopia and become a refugee there."

Civilians escaping government airstrikes and land offensives in South Sudan are taking refuge in makeshift shelters along rivers and crossing into camps in Ethiopia, as analysts warn that a long flawed peace deal has now totally collapsed.

The government, led by President Salva Kiir, has been launching barrel bombs at communities in parts of the northeastern Upper Nile state, since self-defense forces known as the White Army overran a military base in the area in March.

Kiir's regime has also arrested opposition leader and First Vice President Riek Machar, accusing him, without providing evidence, of backing the White Army. It has also bombed bases belonging to Machar's SPLM-IO movement around the country.

Kiir and Machar formed a unity government after a peace deal that ended a five-year civil war, but the president has been accused since then of consolidating power and marginalising the opposition, a process that has accelerated in recent weeks.

Speaking to reporters from The New Humanitarian, civilians in both South Sudan and Ethiopia alleged the national army - currently backed by Ugandan forces - has used incendiary weapons in attacks, and described dire conditions in displacement camps.

"There is no shelter, no food, no medicine," said Nyabhan Guandang*, who escaped to Ethiopia from Nasir, the town where White Army forces overran the military base, but which is now back under government control.

Guandang said her home was destroyed by airstrikes that killed her mother, sister, and two brothers. She fled to the nearby town of Burbeiye, but left for Ethiopia after her children fell sick amid poor living conditions that saw them drinking river water.

The government's attacks have driven more than 130,000 people from their homes, worsened an already widespread cholera outbreak, and badly disrupted humanitarian operations in Upper Nile and elsewhere.

Though White Army forces have retreated in recent weeks after considerable losses, analysts warn of a potential renewed offensive and the rising risk that an expanded conflict could intertwine with the war in neighboring Sudan.

That war has already had a major impact on South Sudan, severely reducing its oil revenues, due to a damaged export pipeline that runs through Sudan. The financial strain has disrupted Kiir's ability to pay off the political and military elites around him.

The president has been sacking key members of his own party and political circle in recent months while also attacking the opposition - actions that may mark the effective end of the peace agreement.

"Machar will fear for his life even if he returns to office and the president will remain suspicious that he's planning to overthrow the government," said Abraham Kuol Nyuon a professor of politics, peace, and security at the University of Juba.

White Army forces attacked the army garrison in Nasir after the government moved to deploy new troops to the area. Locals saw the arrival of these forces - which included militia groups rather than regular soldiers - as a threat to their safety.

Nasir and surrounding areas have long supported opposition forces, and tensions with the army have persisted ever since government troops took control of the town during the 2013-2018 civil war.

The recent airstrikes and ground offensives have further inflamed local anger and driven some 50,000 people into Ethiopia, according to humanitarian workers based in the western Gambella region, where most refugees are escaping to.

The New Humanitarian visited the emergency ward at Gambella Town Primary Hospital last week, seeing new arrivals staggering in, dazed, through dried bloodstains and pools of fresh blood on the floor.

One of the latest arrivals was Gatluak Chuol, a farmer and White Army fighter in his 40s, who said he was shot by men wearing uniforms of the South Sudan People's Defence Forces (SSPDF), the official name of the national army.

Chuol, like many others, said he fled airstrikes in Nasir and sought refuge in Burbeiye, but was forced to flee again after the army raided the town. He escaped via a river on the border with Ethiopia, its waters now rising with the onset of the rainy season.

"They shot at us and bombarded us," Chuol said, looking exhausted, his left arm in a sling and a catheter tube inserted in his right hand. He was one of four people who had just been admitted to hospital.

Ruon Gony, director of the hospital, said 196 wounded people arrived in April alone. Gony said most victims had gunshot wounds, but five suffered burns likely caused by incendiary weapons involving a "black liquid" that blinds and burns human skin.

Nhial Deng, 17, was among the victims of these attacks. He said he was hit while trying to escape from Longochuk, near Nasir, just before midnight on 16 March. He spent three weeks in hospital in Addis Ababa and still has large pink scars on his limbs.

Deng, who is now in the Gambella region, said he feels the South Sudanese government is killing civilians "for no reason other than the fact that we are Nuer", in reference to the ethnic group of White Army fighters and of Machar.

Several refugees said the aerial bombardment is worse than the violence they experienced during the civil war, which killed an estimated 400,000 people and erupted two years after South Sudan gained independence from Sudan.

"I stayed in Nasir during the last war, but now, the clashes are more violent because everyone is targeted, not just members of the White Army," said Guandang, the woman who lost several family members from airstrikes.

White Army forces largely aligned with Machar's SPLM-IO against Kiir's government during the civil war, though independent analysts and experts say the vice president does have control over them and that many fighters criticise his leadership.

Though the force has been accused of atrocities, Guandang said fighters do protect locals. "When women go into the forest to gather firewood, government soldiers beat and rape them," she said. "The presence of the White Army prevents these abuses".

Humanitarian workers in Gambella said refugees are crossing the border daily and are moving into camps that were established by the UN to shelter South Sudanese fleeing the earlier civil war.

The camps have round huts called tukuls built by refugees who never left, yet conditions are poor for the new arrivals, especially amid US funding cuts, which have gutted relief programmes.

Daily rations for refugees have been cut in recent weeks, according to humanitarian officials, and most new arrivals aren't even getting that because they have not yet formally registered.

One UN official, speaking on condition of anonymity, said registration has been slow due to Ethiopian concerns over potential White Army fighters among civilians, and because of doubts that aid agencies have the resources to support new arrivals.

Living conditions are also deteriorating for tens of thousands of internally displaced people who have stayed in South Sudan. Many are sheltering in makeshift sites, where there have been outbreaks of cholera, diarrhoea, malaria, and pneumonia.

Riak Gai, the county commissioner of Ulang, which borders Nasir, said "a lot of children" die every day because of cholera and hunger. He added that civilians avoid fishing in the river due to aerial patrols by the SSPDF and Ugandan forces.

Gatthak Lual, a father-of-three, who fled bombings in his village in Ulang, said people have been fleeing "to areas with no healthcare or water" and that even those with money cannot find food to buy.

"There are no boreholes where people fled to," Lual told The New Humanitarian. "People depend on puddle water or they drink straight from the river without purification."

Chankuoth Duang, a 32-year-old resident of Ulang county, said his family escaped to a remote area after their home in the village of Kuich was bombed in March, an incident that resulted in his uncle being killed.

Duang said he couldn't afford to send his family across the border to Ethiopia, so they have remained in South Sudan, surviving on tree leaves and often going days without food.

"There is no shelter, no clean water, and no humanitarian assistance," Duang said. "In our community, it is very rare for a person to die of hunger. But on the ground, people are starving. Today you can get food, but tomorrow you can't."

Nasir resident Tesloch Puoch said his family is considering leaving for the refugee camps given the conditions they are facing, camped out on a riverbank in Upper Nile with no proper shelter.

"Some [families] live under trees, and if you have a plastic sheet, you build it as a tukul," Puoch said, explaining that every few days, he leaves the camp to find food for his family. "If things don't improve, I'll leave for Ethiopia and become a refugee there."

On top of the offensive against White Army forces, the government's response to the unrest has been to detain key opposition figures - including Machar who is under house arrest - and bombard SPLM-IO bases, including one near the capital, Juba.

Those attacks have led the UN peacekeeping mission in South Sudan to warn that the country "is teetering on the edge of a relapse into civil war", concerns also amplified by the International Crisis Group.

Emmanuelle Veuillet, a postdoctoral researcher at the School of Advanced Studies in the Social Sciences in France and a specialist on South Sudan said the government's actions have rendered the peace agreement "obsolete".

Still, she said it is challenging to call the situation a civil war, "as the opposing side - comprising the White Army and the SPLM-IO - has not launched counter offensives and remains on the defensive against the government's massive and brutal offensive".

Edmund Yakani, a South Sudanese human rights defender and executive director of the Community Empowerment for Progress Organization, said "a lot of energy" will be required to rebuild trust between Kiir and Machar.

He called for transparency in the arrests of opposition members. "If they have substantial evidence, let them produce it before a court of law," he said. "If they don't, let them release them. Political disagreement shouldn't lead to denial of human rights."

Other analysts say the peace deal was never really upheld at any stage, with Kiir's regime instead using the last few years to undermine an already weakened Machar - courting defections and backing militias in violent campaigns against the opposition.

Prior to the unrest in Upper Nile, Kiir, who is in fragile health, had been undermining key elements of the power-sharing accord, while also sacking elites within his own party. Elections, meanwhile, have been repeatedly delayed.

Back in Gambella, several refugees told The New Humanitarian that they feel unable to return to their homes, given what they have lost in the past few weeks and given the risk of more violence.

"I can't return to Nasir as long as government soldiers are there," said 50-year-old Nyariek Tut. She said she lost her four sons when her home in Nasir caught fire during a bombing raid, having previously lost her husband during the civil war.

"They burned houses and killed people," Tut said of the SSPDF, who have also stolen her livestock. "They bombed us. They shot many people. Some fled and others died."

*The names of all survivors of government attacks have been changed to protect their privacy and security. This article was published in collaboration with Egab. Editing by Philip Kleinfeld and Salma Abdallah.