After four years in Sudan's rebel army, Emmanuel Jal deserted with 400 comrades. Only 12 survived, he tells Rob Crilly in Nairobi

There were two choices for the starving boy soldiers staggering through the arid Sudanese bush - suicide or cannibalism. After almost three months searching for safety, the morning dew was not enough to satisfy their raging thirst. Their rations were long gone and the few game animals that lived in the bush had disappeared out of the 40-degree heat. Twelve years later, one of the few survivors remembers his darkest hours.

"Many soldiers became frustrated. They just shot themselves," says Emmanuel Jal, now aged 25. "Others would put their guns to the head of fellow soldiers so that they would fill a cup with urine. We were all ready to die."

Yet, Jal lived. In all, 400 child soldiers had walked out of their barracks one night, sick of the civil war that would eventually kill an estimated two million civilians in southern Sudan. Of the 400, only 12 made it to safety.

Jal was later spotted by Emma McCune, a glamorous English aid worker, who had married a senior rebel commander. She spirited him to neighbouring Kenya where he has forged a new life.

Today he is Kenya's hottest rapper. His debut album is in the local top 10 and I meet him the day before he is due to perform for the president.

"The album is for people passing through hard places, so they know that if they hold on then things will change. And it also spells out my hope for peace in Sudan," he says, sprawling on a cushion in a Nairobi recording studio.

His debut album Gua - meaning peace in his native Nuer language - was released last month and shot to number four in the charts. It mixes staccato rapping in Arabic and English, as well as Nuer, with African rhythms.

"I can't wait for that day when I'll see no more fears, no more tears, no cry," he sings, "no tribalism, no racism in my motherland when my people go back home to their motherland Sudan."

Jal's own flight from the motherland began at the age of seven. Since 1983 predominantly Christian, southern rebels had been fighting the Muslim, northern government. They wanted freedom from Sharia law and control of the region's lucrative oil reserves. The war would become Africa's longest running conflict, forcing more than four million people to flee their homes and pushing a nation into famine.

Three years into the uprising, Jal's father was among the rebels of the Sudanese People's Liberation Army and his mother was dead.

As war closed in on his home in the disputed Bentiu oilfield, SPLA commanders ordered children out of the villages and into the refugee camps of Ethiopia. There the rebels were being sheltered by the despotic regime of Mengistu Haile-Mariam. The camps offered food, safety and schools for the children. But they also hid a dark secret: in reality the camps doubled as recruiting grounds for the SPLA.

Once Jal was eight he was judged old enough to handle a gun. He grins as he remembers the excitement of becoming a soldier.

"We chose the weapon we wanted," he says years later. "I took the AK47 because only the bigger people could manage the big rocket-propelled grenade-launchers." Rebel soldiers would take the young boys deep into the bush, away from the prying eyes of aid agencies or the United Nations, where they would be taught how to strip their weapons and trained in basic battle-craft.

From Ethiopia, they would be sent over the border on raids against Sudanese government troops.

"I was one of the youngest, so I was in the headquarters and would have been among the last to fight. But I would sneak off to fight," says Jal. "If someone saw me there I would be sent back." The eight-year-old was barely bigger than his gun and would close his eyes as he pulled the trigger, such was the deafening roar of the Kalashnikov.

By 1991, the Mengistu regime was on the brink of collapse and the Sudanese children were pushed back into Sudan as Ethiopian rebels closed on Addis Ababa. Jal joined SPLA forces in southern Sudan massing for an assault on the government stronghold of Juba, the regional capital.

"The worst time was when the helicopter gunships attacked. I didn't fear tanks, or the Antonovs, but when the gunships game in below tree-level they would kill many of us," he says. "I would jump in the river and leave only my nose above water so that I could breathe.

"Many of my friends died but you don't feel it immediately. You were too busy trying to survive and you always knew more people would die tomorrow, so you just got used to it."

Today, sitting with a cup of strong, black coffee, he says he has no regrets about fighting.

"I don't know if I killed anyone because I would fight without opening my eyes. But when soldiers go to war, and it is nation versus nation, then the soldiers who are fighting have no sins," he says. "It is the people who decided the war would take place who must answer the questions."

The war was taking its toll on the young soldiers of the SPLA. After four years in the front line, Jal was ready to give up.

"It was too much. It wasn't exciting any more. I wanted to forget it all and just go to school," he says above the jagged bassline pounding through the recording studio.

Almost 400 child-soldiers deserted on a single night. They had saved enough maize and sorghum to last a month, the time they thought it would take to join up with a rival SPLA faction. Their escape involved crossing minefields, and avoiding their former comrades as well as government troops, all in the hottest days of the year.

After almost three months the trek appeared doomed. They were wandering aimlessly, without food, water or hope. One by one they fell.

"I hoped that I would not die, but somehow I also knew that I would survive - even when there seemed no alternative and other soldiers starting eating the bodies of dead soldiers." Only 12 survivors staggered through the gates of Waat, the headquarters of a rival SPLA faction.

Here Jal's path would cross that of Emma McCune, who had caused outrage among the aid community by marrying the leader of the rebel breakaway - Riek Machar. She immediately picked the lively 13-year-old out from the other children. She smuggled him into Kenya, hiding him among luggage on an aid flight.

"She was like a mum - we would sleep in the same bed, she would take me everywhere with her and got me into school," says Jal, remembering the woman who finally helped him escape the war. She later died in a car crash and her remarkable life is now being turned into a feature film by 20th Century Fox and Tony Scott, director of Top Gun. Nicole Kidman is being lined up to play the lead role, according to industry sources.

Today, Jal lives with Riek Machar, who by a twist of fate is a distant relative. They have a house in Kileleshwa, one of the more upmarket areas of Nairobi. Machar remains a leading player in the rebel movement, which is preparing to take power in southern Sudan after a peace deal was finalised at the start of the year.

Meanwhile, Jal is adjusting to celebrity. His hair is freshly cropped and he has taken to wearing a baseball cap to avoid being recognised on the streets. After plans to study engineering fell through, he immersed himself in Nairobi's vibrant music scene, performing at benefit concerts for street children.

He recorded Gua last year, with the financial backing of benefactors in Europe and the US. Since then he has been showered with popular and critical praise.

"Musically his songs are very powerful. Gua is a very powerful song," says Arthur Kamau, producer of Stomp and The Beat, two of the most popular music shows on Kenyan TV. "Then the lyrics are exceptional. They are almost like a prayer in the way that they express how he wants his country to change, the way he wants to see peace and see things back to normal."

But as well as the big picture, Jal says he wants listeners to relate to the smaller picture of personal survival.

"What I have gone through, and where I have been, should encourage other people to realise that they can be saved too."