Juba, South Sudan: In the world's newest country, South Sudanese-Australians are putting the national law of their adopted country to the test in one of the bloodiest conflicts of the 21st century.

It's an offence for Australians to fight in overseas hostilities unless serving in a government's armed forces. The maximum penalty is life imprisonment.

Authorities are aware of "a handful" and "tens" of Australian dual nationals involved in the civil war, sources say, however they're considered a low priority compared to the risk posed by returning Islamist fighters.

The Foreign Incursions and Recruitment law is distinct from the government's Declared Area offence designed to stop Australians journeying to war-torn Syria and Iraq. And no Australian listed terrorist organisations are in South Sudan.    

A rebel soldier stands guard as his comrades arrive at a camp on the outskirts of Juba, South Sudan, in April. Photo: Kate Geraghty

Fairfax Media spoke to a handful of Australian South Sudanese who have picked up weapons and dozens involved in the armed opposition's political wing.

It remains to be seen if authorities will also pursue Australians serving in South Sudan's Army, given the force's widely documented involvement in war crimes.

South Sudan gained nationhood five years ago this month, after a half-century fighting for independence from Sudan. In the 1990s and early 2000s, thousands of refugees from that conflict were settled in Australia.

Rebel soldiers provide security for their chief of staff, Simon Gatwech Dual, as he returns to the capital Juba after the South Sudan peace agreement. Photo: Kate Geraghty

The fledgling country's civil war started in 2013, largely splintering it between the two largest tribes – the Dinka and the Nuer – and between those loyal to President Salva Kiir, a Dinka, and Vice-President Riek Machar, a Nuer.

Both sides are accused of committing atrocities including targeted ethnic killing, rape and torture of civilians in a conflict with an essentially uncounted death toll.

That toll is set to rise as fresh fighting in Juba has again rendered the capital a bloody war zone.

Fairfax Media spoke to six South Sudanese-Australians about their role in the conflict and whether they have a case to answer:

"You can't be picking up biscuits and flowers when people are picking up guns": Agel Ring Machar, 36, from Adelaide, has been on both sides in South Sudan's civil war. Photo: Kate Geraghty

1. Agel Ring Machar

Standing at 208 centimetres, the 36-year-old former South Adelaide Panthers basketballer has been on both sides of the conflict, first as a government soldier and now as a rebel politician.

A "Lost Boy" child soldier in the late '80s, Machar came to Adelaide in 2001. He studied at Flinders University and dated Adut Salva Kiir, the daughter of Salva Kiir, for three years, before the man who is now South Sudan's president expressed his disapproval: "In our culture, when the father says no, your relationship breaks down."

Returning to South Sudan in 2009 to run a humanitarian organisation, he also starred in a documentary about captaining South Sudan's basketball team at independence. A few years ago Machar was shot twice in the leg in Juba by a man he knew over circumstances he won't go into.

Machar, an ethnic Dinka, was the country's National Youth Leader when war broke out in 2013 and he responded to the government's call to arms: "You can't be picking up biscuits and flowers when people are picking up guns," he says, "when there's war, you pick up weapons".

Yet while he was now armed, he says he was too senior to fight.

Machar says he recruited 25,000 to 30,000 young men to the government's armed forces. "You mobilise them to go and fight, it's a war," he says, crediting his recruits with saving the capital Juba from falling to the rebels. Yet a year later he defected.

Shortly after arriving at the rebel camp on Ethiopia's border, a witness says Machar was attacked and detained by a Nuer security officer convinced that Machar had played a part in the ethnic cleansing of Nuer in Juba. The witness says rebel leader Riek Machar personally oversaw the Australian's release and appointed him to a "shadow" governor's position.

Agel Machar admits he helped recruit soldiers who would later become a militia linked to the December 2013 Juba massacre. In 2012, he recruited men from the president's tribal homeland to defend the new country against invasion from Sudan. When that threat subsided, Machar says his role ended. But instead of disbanding the new troops, senior officials close to the president held onto the force and secretly trained them outside of the regular army. "By mobilising those people who were trained and later on came and caused problems in Juba, there is that [personal] responsibility," Machar says. "People don't like that."

During the Juba massacre, Machar says he hid at home with his family before evacuating them to Kenya.

He says he's happy to face questions over his involvement in the conflict. "I'm an Australian citizen, if I'm called in a court of law in Australia to answer a question I will go there," he says. "I believe at the end of the day we'll be found innocent because we came here to contribute positively to the building of the country.

"We the Australians who are involved in this conflict have brought with us the Australian way of doing things. And that is we have tried our best to play fair in this conflict."

"We are not terrorists": Aguer Rual with his Australian passport on the banks of the White Nile in South Sudan. Photo: Kate Geraghty

2. Aguer Rual

A Dinka from Sunshine in Melbourne, Rual arrived in Australia in 2003 and still has family in the city. Fellow community members allege he was a divisive figure, tribally fracturing the South Sudanese community. Rual, however, calls himself a respected community leader. He returned to Africa in 2013 to join the rebels' political movement, motivated, he says, by a wish to help secure peace and stability: "More than 14 from my own family have died in this war."

Rual is a one-time child soldier and politician accused of ruling by the gun. He defected from the rebels earlier this year after returning to Juba with a rebel delegation. While in opposition, he is accused of ordering the execution by firing squad of his colleague, Sebit Magok, who survived to make the accusation. Rual denies the accusation and calls Magok a "liar".

Sebit Majok, 33, accuses Australian citizen Aguer Rual of ordering his execution by firing squad. Photo: Kate Geraghty

Magok claims the incident took place in March 2015 after a disagreement over orders when Rual was a rebel "shadow" governor. Rual was subsequently removed from the position and replaced by Agel Ring Machar (see above). South Sudanese-Australians who know Rual question his mental health.

Rual says Australia's laws prohibiting involvement in a foreign conflict should not apply to him or his fellow dual citizens: "In [the] case of South Sudan, we are not terrorists, we are fighting for the rights of our people."

He acknowledges crimes have been committed in the war but says those guilty should only face consequences in an African court, adding: "I don't think I'm part of that."

"I think it was my responsibility to challenge the regime": Macquarie University graduate and rebel-turned pro-governement soldier, Makuer Mabor Mangar, 33. Photo: Kate Geraghty

3. Makuer Mabor Mangar

When Fairfax Media met Mangar, the Australian fighter had just arrived in the city after two years living in the bush. "I've only just found out that Malcolm Turnbull is Australia's prime minister," he says.

The 33-year-old colonel was possibly the highest-ranking Australian fighting with the rebels before announcing his defection to the government on Monday. A Dinka from Sydney with a dislike of weapons, Mangar has learnt to speak Nuer and claims he was second in command of one of the war's numerous frontlines. Once reported dead by his former rebel side, he tells a story of almost losing his life in battle – "I had to run in a humiliating way. We were surrounded" – and narrowly escaping by crawling to safety through a swamp.

Arriving in Australia in 2006 from a refugee camp in Uganda, Mangar worked at a lamb abattoir in Tamworth before attending Sydney's Macquarie University where he studied policing, intelligence and counter-terrorism. His two wives, one in Melbourne and an unofficial one in Sydney, each have three children. He hopes they will join him to live in South Sudan.

"I miss them, especially my daughters. But I hope they forgive me once they grow up. They will know that what I was doing actually was good for them," he says, speaking at the rebels camp on Juba's outskirts, not far from where his father, a liberation fighter, was killed in 1992.

A photo from Makuer Mabor Mangar's Facebook page showing him (right, in fatigues) fighting for the rebels during the civil war. He has family in Sydney and Melbourne. Photo: Kate Geraghty

Mangar says he's "not worried" about his legal status because he's "fighting a justified war".

"Some people tell me if I go back [to Australia] I will be sued, be jailed. I don't think so.

"Why would you target someone who's fighting a regime [which has] killed thousands of its own people? That would be very unfair to people like me.

"I think it was my responsibility as a civilised person to challenge the regime."

But Mangar has since joined the government Army "under the stewardship" of President Kiir. Explaining his defection in a Facebook post on Monday, Mangar writes: "We cannot go back to bush. I call upon members of the IO [opposition] to reject the repeat of war for peace to reign in our country."

Mangar has no immediate plans to return to Australia and says he "will co-operate" with authorities if need be. "Australia has done a lot for me," he says, "and if you bring that culture [to South Sudan], that civilisation to this country, I think this country will be a great country".

"I remained a soldier and that's what I currently do": Angelo Kuot Garang, 33. Photo: Kate Geraghty

4. Angelo Kuot Garang

Arriving in Adelaide in 2003 after schooling at a refugee camp in Uganda, Kuot (spelt Kout on Australian records) later moved to Melbourne to study environmental science at Swinburne University. In 2006 he joined the Australian Defence Force "to say thanks to Australia". Serving most of his seven years with the 2RAR regiment, he saw deployment to the Solomon Islands and East Timor.

Garang later completed a master's degree at the Australian National University in Canberra before landing an environmental health officer's job with Brimbank City Council in Melbourne. He returned to South Sudan in 2012 to set up an Australian-partnered public health company but the civil war cut those plans short. "I came back because I wanted to be part of the future of this country, if it has one," he says, but adds, "when war broke out … I had to join the armed force [sic] to defend the constitution".

Angelo Kuot Garang (in sunglasses) at Juba airport awaiting the return of rebel leader and South Sudanese Vice-President Riek Machar. Photo: Kate Geraghty

Kuot first took up arms when he joined the Red Army – a force of child soldiers trained by the South Sudanese when they were fighting the Sudanese government – as a 10 or 11-year-old and took part in the battles for Juba in 1991. "This is not the first time I fought for SPLA. I was born there and I grew up there. I am part of the making and I am still part of the making [of South Sudan]," he says.

He is confident he's on the right side of the law. "It is not illegal. I have dual citizen [sic] and I can serve in my country, that's fine. The same way I can serve in Australia."

The 33-year-old hopes to return to his public health company plans, but not immediately: "I remained a soldier and that's what I currently do."

"I'm worried, maybe they are going to arrest me": General Gabriel Gatwech Puoch Mar, 55, sits in a hotel in Juba. Photo: Kate Geraghty

5. Brigadier-General Gabriel Gatwech Puoch Mar

A veteran among South Sudan's liberation war veterans, the 55-year-old general lived in the Melbourne suburb of Berwick from 2001 to 2003. His family are still in Berwick and he visits regularly.

When war broke out, he says he was the chief administrator of the Army's 5th Division in Wau, a non-combatant role in a region he says avoided the ethnic killings that swept the country. Puoch, a Nuer, stayed almost 18 months with the army before defecting to the opposition after being overlooked for promotion. But a few months later he changed sides again, walking away with two dismissed rebel generals who set up their own party.

Now head of security for the "armed forces" of the Federal Democratic Party, Puoch is serving his third army in three years.

General Gabriel Gatwech Puoch Mar, who lived in the Melbourne suburb of Berwick, has been in three armed forces in three years. Photo: Kate Geraghty

"I have not read the Australian law which shows you cannot go to war," he says, adding that he thought the law only applied to militants fighting with the likes of al-Qaeda and Islamic State. "I'm worried, maybe they are going to arrest me because my name was spoiled as someone who went to the rebel side and fought," he says. "As far as I know I did not commit anything. I did not go to any war.

"If they ask me to explain I will explain to them."

Australian citizen Yien Oral Lam, 48, from Alderley in Queensland, is seen here in his blue police uniform and beret at a ceremony to welcome rebel chief of military staff Simon Gatwech Dual back to Juba. Photo: Kate Geraghty

6. Lieutenant-General Yien Oral Lam

Coming to Australia in 1998, Oral Lam studied law at the University of Queensland and says he later worked in Queensland's Department of Justice. In 2006 he joined the United Nations as a Rule of Law Officer and found himself working in South Sudan.

The former Khartoum policeman was his country's top cop – at least on the opposition side – before the latest fighting erupted. One of the first men to greet the rebel army chief on his return to Juba, Oral Lam stood out in his crisp blue police uniform.

A "focal point in security arrangement" was how the 48-year-old from Alderley in Brisbane explained his job with the rebels. He says he was establishing his own law firm in Juba when war broke out in 2013. "We were in a house in the most dangerous area" of Juba, he says, speaking of the suburb of Gudele, where Nuer civilians were killed in door-to-door searches.

Asked if his "security sector" position comes under the rebels' political movement or their armed wing, he answers: "We are ... all together, it's the one entity. You don't divide them." The response is at odds with most rebels Fairfax Media spoke to, who identified only under the political wing for fear of breaching Australia's foreign fighter laws. "I don't see [that] the law is relevant to us South Sudanese," Oral Lam says.

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