Luther is bored now with questions and wants to play with the tape recorder. "Give it to me and I will take it into the battle. I will tape the sounds of fighting on the battlefield and when we capture a Burmese soldier I will ask him questions and give it to you."

There was nobody with a tape recorder to tape the sounds of the Burmese army arriving at the village of Ler Per Her 10 days ago. The only sound there now is the plop, plop of giant raindrops dripping through the holes in the roof of the schoolhouse that the army burned down.

Now, like the other Karen villages that once lined the route of the pipeline, Ler Per Her is near-deserted. Its only remaining inhabitant, a woman named Wah Wah, is cooking rice in a hut in the afternoon downpour. She is tired of running: over the past 10 years she has been driven from four villages by the Burmese army.

This time, she says, the attack came at 3 p.m. "It was a Sunday. Everyone panicked and started running for the river. There were nearly 2,000 people in this village, but we had only three canoes. People were throwing their children on to them and loading them down to within an inch of the water. Some people didn't wait for the canoes, they just panicked and started swimming."

Wah Wah had five children, but in the decade she has spent on the run from the army, four of them have died. "They died from illnesses that I couldn't get medicine for because we were hiding in the jungle," she says. "Do you know what age they were? One was eight, two were four and the other one was one and a half."

Across the river that marks the Burma-Thailand border, Dr Bill Greiser of the Christian fundamentalist group Strategic World Impact is one of the few aid workers treating the Karen who have escaped.

"There's malaria, there's malnutrition, but mostly they are chronically depressed - they've been running like this for years." A preacher, a tall American in his 30s, calls on these wet, miserable people who are covered in jungle muck to stand up and "take the Lord into their hearts". Under the leaking bamboo shelter, he shares out anti-malaria pills with his big, warm, white American hands, then raises them towards the roof and cries: "We thank the Lord for bringing us home to you."

It was in a heaving, overcrowded refugee camp that Luther's bodyguard, Rambo, found God three years ago. He wears his Bible around his neck in a green silk purse. His only other valuable possession is a Burmese passport carefully wrapped in plastic that tells him he is a citizen of a country he is not allowed to live in.

"Other young Karen men like me are trying to get out, to go to Australia, but God has told me to fight for my country and to follow Luther and Johnny." It is Rambo's job to translate the scriptures that the illiterate Luther can't read. He opens his Bible and in a halting, reverent voice reads from the Book of Corinthians.

"`But God hath chosen the foolish things of the world to confound the wise; and God hath chosen the weak things of the world to confound the things which are mighty.'

"That's one of his favourites," says Rambo, searching again through his Bible wrapped in paper with pale pink roses. "He likes this one as well. Timothy, chapter 6, verse 12: `Fight the good fight, lay hold on eternal life, where unto thou art also called."'

When Luther is faced with a difficult question he turns to Rambo. On philosophical matters he is vague. "I say my prayers and the Lord inspires me." "What prayers do you say?" "I can't remember them."

"Why did God choose you and your brother?" Luther looks puzzled and Rambo fills in: "God chooses the weakest to do his best for the people. It matches with what God says in the Book of Corinthians, chapter 1, verse 27."

On military matters, Luther is more precise. "We have lost 13 of our God's Army soldiers. They sacrificed themselves in the battle. Two of them were children. No, I am not afraid. I am serving my people."

"Have you been wounded?" "No, the Lord has protected me." Beneath his eye is a round scar. "We were playing with bamboos," he says. "Someone scratched my eye." Johnny, who is in charge of food supplies and logistics, sits beside his brother and plays with a catapult.

Even with God behind them, Luther and Johnny Htoo can't fight the gas pipeline that brought 10 Burmese infantry battalions to their land. By January this year there were 21,000 troops in an area where there had once been 1,500. "Economically, the gas pipeline had to go through at all costs," says Sister Mary Roberts, a Catholic nun from California who arrived in the area from China in 1951.

"The military used forced labour to clear the forests, people were kidnapped to work as porters and build the military security camps. They were being wiped off the land and nobody was helping them. In the daytime, the women were taken to work as porters for the army and at night they belonged to the soldiers.

"The oil companies were very clever. They let the Burmese military do the dirty work and then pretended they didn't know anything about it."

Premier Oil, the British company running one of two pipeline consortiums cutting through the Karen area, said it knew there were human rights abuses by the military and condemned them.

Chief executive Mr Charles Jamieson also said: "We're satisfied that human rights abuses aren't taking place in the area we are responsible for. If we come across them we report them to the relevant authorities. Premier believes in constructive engagement with the regime - not empty rhetoric," he added.

The Jubilee Campaign, the human rights organisation based at Westminster and campaigning for the Karen, says: "It is a nonsense for Premier to report abuses to the `relevant authorities' - the `relevant authorities' are the Burmese military. Premier should admit they are working with mass murderers."

The Jubilee Campaign claims that at least 30,000 Karen people have died in the military's secret genocide against these people.

Johnny and Luther have tired of sliding on the cardboard box and now the saviours of the Karen people are splashing in the river with other boys, just a little older, all lost in oversized military shirts from Thai army surplus shops. Their old Vietnamese guns lie abandoned on the river bank.