The scene on the edge of Colombia's northwestern Catru indigenous reserve, home to the country's Embera Indians, appears almost idyllic. Children splash and laugh in the river, while others play football on a sandy bank. Embera women chat leisurely as they wash colourful clothes against the backdrop of lush mountains.

But a very different scene unfolds inside the reserve lying in Colombia's western province of Choco, a far-flung jungle region near the Panamanian border.

In March, more than 800 Emberas fled their rainforest homes along the Baudo River to Catru, to escape a drug turf war between the National Liberation Army (ELN) guerrillas and criminal gangs.

Violence in Colombia, where Revolutionary Armed Forces of Colombia (FARC) rebels have waged a four-decade-old guerrilla war, has fallen in recent years thanks to a U.S.-backed security push that has pummelled the FARC in many parts of the country. And the fighting has become little more than a battle for control over cocaine-smuggling routes.

The Emberas say two community teachers were beaten up by the "Los Rastrojos", a local private army of 1,000 or so thugs linked to paramilitary groups and at the service of powerful drug lords.

"They've accused us of helping the guerrillas and providing them with food," Gabriel Forastero, a leader of the Emberas told AlertNet as he took shelter from the rain in his wood HUT. "They've threatened to kill anyone who they wrongly believe is collaborating with the guerrillas."

Fear and panic quickly spread among the Emberas as they witnessed groups of armed men suddenly moving along the rivers, while others say gunmen entered their homelands, prompting them to flee and find shelter in Catru.

"No-one dares to be around when those groups start fighting with each other," said Forastero. "We end up paying the price."

UPROOTED FAMILIES

The Emberas' displacement marks one of the biggest of an indigenous tribe in Colombia in more than a decade.

The Latin American country has the world's biggest displaced population after Sudan - a United Nations-backed report released this month put the figure at 4.3 million, although the Bogota government estimates it at around 2.5 million.

And the numbers continue to rise.

Colombia's main rights organisation, the Human Rights and Displacement Consultancy (CODHES), reported in April that more than 380,000 people were uprooted from the homes last year - some 24 percent more than in 2007.

Most were forced out by fighting between the army and the FARC, the rearming of far-right paramilitary groups that had demobilised and fear over child recruitment.

For the Emberas, there is little doubt that their fate is linked to Colombia's cocaine trade, which accounts for some 60 percent of the world's cocaine production.

The Baudo River and its tributaries are lifelines for the Embera and Afro-Colombian communities living here, along which plantain, timber and fish is traded. But because these waterways feed into the Pacific Ocean, they are also a much-coveted strategic corridor for drug traffickers.

Increasingly drug barons are using the sea to transport cocaine through the Pacific, with Central American countries being used as transit points from where Colombian cocaine is then picked up by Mexican cartels.

"The fighting we're caught up in, is all about cocaine," said Casildo Forastero, an Embera leader. "With the Pacific nearby, the drug barons have an exit to the world."

WHAT HAPPENS WHEN THE FOOD RUNS OUT?

As the days roll on at the Catru reserve, pressure on food supplies is growing as are tensions between large families forced to live together in cramped huts along with roosters, hunting dogs and roaming pigs.

"My relatives I'm staying with have enough rations for their own family, but not for the three displaced families living with them too," said Emerson Chamorro, a young teacher who like many displaced Embera found shelter with relatives already living in Catrú.

Humanitarian aid such as rice, baby milk formula and medicine from both local and international agencies, including the U.N. refugee agency (UNHCR), has arrived at the reserve. But community leaders representing the 1,800 Emberas settled here, fear for the future.

"The food we've been given will last another month, and then what happens?" said Forastero.

Medical charity Medecins Sans Frontieres has identified 35 cases of malnutrition among Embera children.

With permission granted by Embera leaders to enter their reserve, government troops have set up a temporary base in the surrounding hills overlooking Catru and heavily armed soldiers are on daily patrol to repel attacks against the tribe.

The Colombian armed forces have now reached most of the 15 villages from where the Emberas fled. The army says it has control of the area and has set checkpoints along the river banks.

After being forced away from their homes for over seven weeks, in recent days many of the displaced Emberas have been preparing to return to their homelands, while others have decided to settle on undeveloped lands nearby. Wherever they end up, the Emberas will have to start again from scratch.

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