HE survived decades of Colombia’s murderous guerrilla uprisings. He lived through paramilitary purges and steered well clear of the cocaine overlords who swarmed across his rural region. It was something completely different that killed Innocence Dias. He died because the world is turning green.

The global quest for alternative sources of environmentally friendly energy has attracted high-profile support from American politicians, including President George W Bush and Arnold Schwarzenegger, the governor of California. Celebrities such as Daryl Hannah, the actress, and Willie Nelson, the country singer, are leading a campaign to promote green fuels.

Yet the trend has already had disastrous consequences for tens of thousands of peasants in rural Colombia. A surge in demand for biofuels derived from agricultural products has unleashed a chaotic land grab by a new breed of gangster entrepreneurs hoping to cash in on the world’s thirst for palm oil and related bioproducts.

Vast areas of Colombia’s tropical forest are being cleared for palm tree plantations. Charities working with local peasants claim that paramilitary forces in league with biofuel conglomerates – some of them financed by US government subsidies – are forcing families off their land with death threats and bogus purchase offers.

“The paramilitaries are not subtle when it comes to taking land,” said Dominic Nutt, a British specialist with Christian Aid who recently visited Colombia. “They simply visit a community and tell landowners, ‘If you don’t sell to us, we will negotiate with your widow’.”

Dias was one of several landowners around the remote settlement of Llano Rico who decided not to abandon his property when the paramilitaries first moved into the area. “My father felt protected because he had a local government position,” said his daughter, Milvia Dias, 29.

Even when paramilitaries warned the villagers that if they stayed they would be considered left-wing guerrilla sympathisers, Dias refused to be bullied. “He had cattle and land and one day, after all this happened, he went out to fix a hole in one of the farm’s fences,” his daughter said. He never came back. A search party found him with his throat cut and seven stab wounds in his torso.

“We held the funeral at 5pm the same day and we ran away the next morning,” said Dias. The land is now covered in palm trees owned by Urapalma, a Colombian enterprise that has repeatedly been accused in court proceedings of improperly invading private property.

Nutt said last week that he had heard stories of paramilitaries cutting off the arms of illiterate peasants and applying their fingerprints to land sale documents. In many cases, Nutt added, the land is collectively owned by indigenous people or Afro-Colombians and protected by federal laws that courts seem unable or unwilling to enforce.

There is no reliable estimate of how many thousand acres have been appropriated, or how many of the 3m Colombians who have lost their homes since 1985 were forced out by the palm oil business.

Washington has been struggling for years to persuade Colombian farmers to turn their backs on coca leaf production in favour of other crops. Desperate to find energy alternatives to expensive and politically volatile sources of Middle Eastern and Venezuelan oil, Bush is also advocating a global increase in biofuel production.

Alvaro Uribe, the president of Colombia, has urged local palm oil producers to more than double the land they have under cultivation within four years. Uribe’s critics complain that he has effectively given a green light to paramilitaries.

At a congressional hearing on Colombia last week, Luis Gilberto Murillo-Urrutia, the former governor of Choco province, told a House foreign affairs subcommittee that US trade policy was likely to “generate an expansion of palm oil cultivation in Afro-Colombian territories . . . there is evidence that palm oil companies, taking advantage of the vulnerability of Afro- Colombian people, have been taking over lands illegally”.

For Don Enrique Petro, 67, formerly a wealthy landowner from Curvarado, growing international awareness of the human cost of a green conscience has come several years too late.

“I arrived in Curvarado 39 years ago with my wife and five sons,” he said last week. He bought a patch of jungle and slowly transformed it into a 30-acre spread with 110 cows, 20 bulls and 10 horses.

He lost two sons and a brother to the guerrilla wars and in the early 1990s fled his land for five years. When he returned, he found a right-wing paramilitary group in control. “They said they wanted my land to fight the guerrillas,” Petro said. “They were lying. It was so they could grow palm on it and make money.” Petro refused to sell up. He claims he was eventually taken prisoner by the paramilitaries and, when released, found his land had been planted with palm trees belonging to Urapalma. The company has denied that it is cooperating with paramilitaries or acquiring land illegally.

The world’s demand for alternative fuels is unlikely to diminish, but Nutt argued that biofuel consumers should put pressure on Colombia to return stolen land.

Celebrities such as Hannah are beginning to distinguish between palm oil and less controversial biofuels such as ethanol, which is derived mainly from corn.

“I want biofuels that are grown and produced in a sustainable manner,” said Hannah, who leads a pressure group which is lobbying for US government standards on green fuel production. “I would not buy biodiesel made from palm oil.”

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