KATHMANDU, Nepal – The southern plains of Nepal, which share an open border with India that stretches hundreds of miles, have long been a haven for marijuana farmers.

But as U.S.-led forces strike back against opium growers in Afghanistan, demand from India has turned the Terai region of Nepal into a burgeoning hub for the opium trade.

"Till now, there are no big gangs like in Mexico or Colombia. They are small farmers," a senior police officer told GlobalPost. "But tomorrow, it will be organized."

Once restricted to small pockets in the Parsa and Bara districts, this season’s poppy cultivation was prevalent in 25 of 82 villages, accounting for more than 1,500 acres of farmland. For the worldwide opium trade, that's nothing compared with the hundreds of thousands of acres devoted to poppy growing in Afghanistan — which still accounts for 90 percent of the world's supply, according to the United Nations.

But the new threat is nevertheless a major headache for officials in India and Nepal who are concerned about the spillover effects of the illegal trade — including an increase in organized crime and better financing and arms for local insurgent groups.

"My experience is that the trend is increasing," the police officer said. "If you go three or four years back, it [opium farming] was only in Parsa, but now it has spread into Bara and other districts."

According to the Kathmandu-based police officer, who asked not to be named because of restrictions on talking to the foreign media, the marijuana trade flourished in this area because of a power vacuum created during Nepal's 10-year civil war. Although the war ended in 2006, higher profit margins have tempted the farmers further into the opium business, while local corruption and central government malaise prevents any meaningful efforts at halting it.

"We have known [for some time] that even law enforcement officials and other administrative officials and local politicians – all of them profit from this business," the police officer said.

The latest World Drug Report from the U.N. Office of Drugs and Crime ranks India among the largest consumers of heroin in the world. Nepalese law enforcement officials said the demand creates a back-and-forth trade in raw opium and low-grade "brown sugar" between the two countries, whose citizens are allowed to cross each other's borders without a visa — and often without any kind of identification at all.

On the Indian side, Bihar is one of India's least developed and (until recently) worst-administered states. And in Nepal, though peace has returned, there's hardly a government at all.

After the end of the civil war, Nepal abolished its monarchy. Elections two years later installed Pushpa Kamal Dahal, the leader of the Maoist rebellion, as prime minister of the new republic. But since the war ended, a sometimes violent ethnic identity movement has begun. Prachanda and the Maoists have quit the government, and legislators have failed to agree on a new constitution —leading to a crisis of instability in which the bureaucrats, police and politicians of the hinterland are left to their own devices.

In recent months, for example, the country has been in limbo following the resignation of Prime Minister Madhav Kumar on June 30. After legislators failed to form a new government despite 16 rounds of parliamentary elections, the interim administration faced a funding crisis until last week because no national budget had been approved.

Though the local trade is small compared with global statistics, Nepal is a small country, and the intersection of armed insurgents and drug traffickers is already emerging to blight its southern plains.

With a veritable alphabet soup of rebel groups operating in the area, kidnapping and murder is rampant. And, as a series of executions of school teachers in recent years shows, nobody is safe from the mayhem.

"Where insurgencies are flourishing, opium cultivation is encouraged," said the police officer. "Now the international security forces are concentrating [on interdiction efforts] in Afghanistan, so we suspect more opium cultivation will be shifting toward Nepal."

For local farmers — and, often, the police — the profits are simply too big to pass up. According to local reports, a fertile acre yields between 3 and 9 kilograms of opium per year, and even the unprocessed opium brings $800 to $1,000 a kilo from traders in India, where illegal processing laboratories speedily turn the raw product into morphine and heroin, which sells for as much as $90,000 a kilo.

And that means payoffs are easy. It costs less than $10 an acre to convince the police to look the other way.

Officials say they're doing as much as they can, and it's impossible to control the trade when virtually every field of sugarcane has a poppy crop hidden in its center. This year alone, the police have destroyed 270 hectares of poppy fields, the Kathmandu Post reported, quoting the chief district officer of Bara as saying, “We will charge anyone who’s found to be cultivating or transporting opium.”

Yet the crime statistics are not encouraging. Not a single farmer has been charged with poppy cultivation in the district this year, though police said Bara alone must have produced nearly $7 million worth of opium this year, according to the Kathmandu Post.

Anil Giri contributed reporting for this article.

Editor's note: This story was corrected to remove the names of the Madhesi Janadhikar Forum (MJF) and Terai Madhesh Loktantrik Party (TMLP), which were incorrectly identified as rebel groups in the original version.