Yiech Pur Biel was 10 years old when his mother left him.
"I wanted to go with her, but a man prevented me," Biel said, remembering that morning in 2005. "'If you accompany her,' he said, 'I will beat you.'"
The man restrained Biel at the urging of the boy's mother, who'd been forced to make the most painful of choices as she fled her home in southern Sudan. Her family's grass house had been repeatedly burned to the ground by the Sudanese army. The soldiers had torched the whole village and shot scores of peasants.
It was the culmination of Sudan's civil war, which lasted more than 20 years and caused an estimated two million deaths, with the violence continuing even after South Sudan became a sovereign nation in 2011.
Biel's mother was trying to escape to Ethiopia. But could she feed all four of her children en route? Couldn't the oldest, Yiech Pur Biel, survive on his own by finding food in the bush? She left him. As she disappeared down a footpath, Biel remembers her crying out: "I will see you again very soon."
Biel has not seen his mother since then. He does not know if she is alive.
He will be thinking of her when he makes history in Rio de Janeiro. An 800 meter runner, Biel is one of 10 athletes on the first refugee team to compete in the Olympics. Unaffiliated with any nation, the squad also includes two Syrian swimmers, two Congolese judo players and an Ethiopian marathoner who fled to Luxembourg.
At the team's core are Biel and four other South Sudanese middle distance runners, all of whom live together at a bare bones training camp just outside Nairobi, Kenya. It is a one-time orphanage in the Ngong Hills, where they train together on red clay paths, weaving through corn and potato fields, ducking under wire fences and trotting past herds of cattle and goats.
The South Sudanese Olympians -- three men and two women who will compete in the 400, 800 and 1500 -- are newcomers to track and field. Until 10 months ago, Biel had never owned a pair of running shoes, and he was not sure which way to circle the track in races. He was, however, very fit. He was a talented soccer player, a sandlot star at a northern Kenyan refugee camp. His stride was silken and long-legged.
A devout Christian, Biel sang in a Baptist choir, and he harbored giant dreams of becoming a humanitarian.
"I don't want other people to suffer as I have suffered," he thought after finishing high school last year. "I want to help people. I want to study international relations and then go home to bring peace to South Sudan."
There are now more than 65 million refugees on earth, the highest number in history. Most of them are young, and most are isolated and mired in poverty, unable to tap their potential.
Until last fall, Biel was likewise stuck. He was killing time with no money for college. Along came a Kenyan runner, Tegla Loroupe, who in the mid-1990s was arguably the world's premier female marathoner. Now 43, Loroupe has spent the past decade working as a peace activist.
In late 2015, Kakuma, the refugee camp, swelled with nearly 200,000 residents, according to the United Nations High Commission for Refugees. Most of them were South Sudanese, and Loroupe felt sympathy.
"Any one of us could be a refugee," she said. "I was displaced once myself, in 1999, when all 40 of my cows were stolen away to Uganda. These refugees, it wasn't their wish to be put in a camp, and they need our help."
Loroupe decided she would give Kakuma something to be proud of. She started a running team composed of refugees, and on a hot day last September, she hosted three time trials at the camp. She asked the young athletes to run either 5 or 10 kilometers on a dirt road.
Biel ran the 10K. He ran it barefoot.?He had never run more than a mile without stopping.
"I felt like I was going to collapse," he said.
He finished in 35 minutes. He was more than eight minutes off world-record pace, but his time would have placed him amid the top 1 percent of Americans who entered a road race last year. He placed third out of 100 in the Kakuma race and made the team.
Loroupe, in her generosity, elected to bring 27 Kakuma runners to her rustic camp in Ngong, and for many, the rigors of daily training were overwhelming.
"I'd wake them up in the morning to run," said Joseph Domongle, a Kenyan coach at the camp, "and they'd say, 'I'm too tired.' When I'd ask them to run a hill 10 times, they'd do it twice and sit down, saying, 'Who are you to tell me what to do?'"
Thirteen athletes returned to Kakuma. Biel stayed. He bunked with three other runners in a cramped, barren, concrete dorm room. He ran three times a day. He finished his first 800 on the track in 2:08 and gradually whittled his time to 1:57, which would have been faster had two campmates not halted, mid-race, in his path.
He watched the news in the camp's TV room. He strolled into Ngong town and bought stalks of sugar cane for 20 cents and hung out with friends in a pasture. When it cooled one evening, he set a battered school chair on the camp's rough lawn and sat down. Bony cows strayed in from the dirt road nearby to pick at the grass before meandering away in the fading light. Biel relaxed and remembered his earliest days.
"I had a lovely father," he said. "From the time I was 7, I would work with him, taking care of the cattle, the sheep and the goats. He taught me to fish in the river, and every evening after supper, he would call us to the fire to tell us stories -- fables about animals. He told me, 'If I'm not around, you'll have to care for your siblings. Now that you're working, you are a man.'"
Biel was only 8 at the time, and according to the traditions of his tribe, the Nuor, he was still a boy. Nuor males become men only when their brows are incised with a knife, to form a gar consisting of six parallel forehead scars.
Why was his dad saying this? It's impossible to know.
Before Biel turned 9, his father was gone. Did he leave home to fight in the war? Was he captured by the Sudanese Army? Biel's mother was never sure. She just waited for her husband to come home.
"Five days became a month," Biel said. "Then it was two months."
Meanwhile, the north Sudanese soldiers began infiltrating Biel's village, outside the larger town of Nasir, via underground tunnels. At night, they hovered overhead in helicopters, then dropped explosives that set the huts ablaze.
"Most nights," Biel said, "we went into the bush."
He has no idea how many times his mother took the family into the bush, away from the explosives and gunfire, when he was 8, 9 and 10 years old.
After each helicopter attack, Biel slept on the ground for several nights -- or rather, tried to sleep as the mosquitoes hovered around him. The snakes scared him; he was afraid the lions would attack. To survive, he ate any fruit he could find, "even if it was poison," he said. Routinely, he ate leaves. As the soldiers burned crops, there were simply not enough calories available.
"The population was very high," Biel said. "Only the strongest were going to survive."
By the time his mother left in 2005, after two years of military assaults, many of Biel's fellow villagers had starved. But the biggest threat to Biel was the guerrillas fighting for South Sudanese independence. As they battled against the Sudanese army, the rebels began sweeping into southern villages, seizing boys as young as 8 to serve as soldiers.
In March 2005, two months after his mom's departure, a UN official recognized Biel's vulnerability and made sure he relocated. As he rode north, he felt guilty, he says. Shouldn't he have been back in South Sudan, waiting for his dad to return?
Kakuma, the refugee camp, was safe. But at first, water was scarce. Often, it was so dry that the refugees had to dig in the mud for water. When the UN installed running water at Kakuma, it was sometimes available only for brief windows of time. Some days, Biel waited at the tap for hours, only to be sent home empty-handed. At times, dark confusion and pain swept over him.
"It hurts me to live without parents," he said.
About a year ago, however, a relative of Biel's visited South Sudan's capital, Juba, and talked to him. He reported that both of Biel's parents are still alive, as are all three of his siblings, as well as two new ones. Biel doesn't believe it, though.
"When you're far away, they don't have to tell you the truth," he said. "I think he was just trying to make me feel good."
Even if Biel's family was OK a few months ago, that was a few months ago in a part of the world where conflict is a constant. Since South Sudan became independent five years ago, it has been riven by tribal warring. Since 2013, one power struggle -- between Biel's tribe, the Nuor, and the ruling Dinka -- has claimed at least 50,000 lives and displaced more than two million in a country of just over 11 million people.
The U.N. has called South Sudan's new civil war "one of the most horrendous human rights situations in the world," and even for South Sudanese who have fled their homeland, this war is impossible to ignore. As one of Biel's fellow runners, Puk Deng, lounged on the grass in Ngong recently, he called family in Juba, only to learn that his 19-year-old nephew had been killed.
"There was fighting behind the UN compound in Juba," he said. "He hid under his bed in his hotel, but they found him and removed him and shot him."
Biel is afraid to go back to South Sudan.
"In Juba, they will kill me," he said. "They will know I am Nuor in a moment. Even if you don't have the gar, they know. They ask you to open your mouth and speak Dinka, and if you can't, they kill you."
The Dinka and the Nuor have a long history of minor conflict, mainly over cattle and land, but their relations have often been peaceful, and recently, as Biel rode a team van home from a tough workout, he was playfully slap fighting with his two female teammates, both of whom are Dinka.
"Do you like those girls?" someone asked. Biel ducked his head bashfully, his teeth glinting as he smiled. "They are like sisters to me," he said.
The next morning, he headed out for an easy, 45-minute jaunt. Then lunch, a few scraps of goat meat on a heap of white rice, and that afternoon, he and his teammates laced up their bright, new running shoes, donations from Germany, before loping along through the corn fields toward a dirt track in the hills.
When Biel steps to the line in Rio's Olympic Stadium on Aug. 12, he hopes to drop his time to 1:49. Such a vast improvement -- eight seconds over 800 meters -- would border on miraculous. Even so, had Biel run 1:49 at the London Olympics four years ago, he would have finished about 40th out of 52 finishers in the first round. The world record for the 800 is 1:40.91, set by a Kenyan, David Rudisha, at the 2012 Games.
Perhaps it doesn't matter how Biel finishes at Rio.
"We're going there to the Olympics to tell our message," he said. "Some people, when you say the word 'refugee,' they think, 'They are violent.' We will show the world that as refugees, we can do anything that a human being can do. Being a refugee is not the end of everything. We will tell that message to other refugees, and it will open doors for them. It will give them hope."
For Biel, hope has already taken root. It happened in June, when he was named to the Olympic team.
"There are two times in my life that I've cried," he said. "When my mother left me and when I was chosen to go to be on the team."
Currently, Biel is hoping to find a running sponsor. "Visa maybe, or Adidas," he said, only vaguely familiar with the corporate landscape. He also hopes that somehow he'll find funds for college. "God willing," he says, "going to Rio will open a way for me."
But what Biel most longs for is a reunion with his parents. At some point, he said, he will go back to his village to look for them, even if that means touching down at the Nasir airstrip for an hour or two to search.
"I could not stay," he said. "It is too dangerous, but I need to go, for it is my duty to find them."