PLATTSBURGH, New York - The world's longest undefended border.

It's a catchy yet increasingly imprecise term for the U.S.-Canada frontier, as authorities on both sides ratchet up efforts to curb bustling traffic in illegal drugs and guns.

The U.S. Border Patrol has tripled the number of agents along the 8,851 kilometre border in recent years, with hundreds more soon to be deployed. Unmanned U.S. surveillance aircraft are being tested for use over the frontier, and video surveillance towers are going up around Buffalo and Detroit.

Multi-agency, binational law enforcement teams operate in 15 regions from coast to coast.

The U.S.-Mexico border draws far more attention in the U.S, and more American resources, as Mexican drug cartels fuel killings and corruption with massive trafficking operations. Thousands of Mexican troops battle the cartels in a conflict that has killed more than 11,000 people since late 2006.

By comparison, the scale of drug violence and trafficking in Canada is minuscule. Yet the northern border, mostly out of the spotlight, presents its own challenges -- hard to monitor due to its length and geography, used by a diverse array of traffickers ranging from outlaw motorcycle gangs to Asian-run drug rings.

"It's a long border, mostly very remote, very wooded, very sparsely populated," said James Burns, the U.S. Drug Enforcement Administration special agent in charge of upstate New York. "It's easy to go from one side to the other without detection."

Canada supplies large quantities of marijuana to American users, including hundreds of thousands of kilograms a year of lucrative, high-potency "B.C. Bud" from British Columbia. Canada also has developed rapidly into a leading supplier of ecstasy, often laced with highly addictive methamphetamine, both for U.S. and overseas markets, as crime gangs operate factory-style superlabs.

The contraband arrives by helicopter, boat and float plane, in cattle trucks, hikers' backpacks, and by snowmobile. One favoured smuggling passageway is the St. Regis/Akwesasne Mohawk Indian reservation straddling the St. Lawrence River along the New York-Canada border -- tribal sovereignty limits access by Canadian and U.S. investigators.

Just this month, federal and state authorities in Plattsburgh, on the western shore of Lake Champlain, announced the dismantling of an alleged billion-dollar marijuana smuggling ring that used the Mohawk land as a transit route into the United States.

Operation Iron Curtain resulted in charges against more than 45 people from Quebec to Florida. Over the past four years, the ring allegedly smuggled about $250 million worth of high-grade, hydroponic marijuana into the U.S. annually.

"It's easy to forget in these idyllic surroundings and friendly communities and with our close relationship with our Canadian neighbours that there are people so interested in lining their own pockets that they don't care what harm they cause others," said Assistant U.S. Attorney Grant Jaquith.

Even excluding the remote 2,414 kilometre border with Alaska, the U.S.-Canada frontier covers 6,437 kilometres from the Atlantic to the Pacific -- twice as long as the U.S.-Mexico border.

Yet as of last month, the Border Patrol had 16,900 agents deployed along the Mexican border and 1,550 along the Canadian border. That northern contingent is up from less than 500 agents in 2002, and will expand to more than 2,200 over the next year.

At last count, marijuana from Canada accounted for less than three percent of the pot seized near U.S. borders, with the bulk coming from Mexico. But the D.E.A fears more will be coming from the north as marijuana-growing operations expand in eastern Canada.

Other trends also cause alarm. Seizures of ecstasy being smuggled from Canada to the U.S. quintupled between 2004 and 2006, from 1.1 million dosage units to 5.2 million. Meanwhile, Canadian authorities reported that seizures of cocaine coming northward over the border had tripled.

The boom in Canadian ecstasy smuggling followed a cutback of the drug's production in Western Europe, and is linked to the ability of crime groups to bring precursor chemicals from Asia into Canada for processing at gang-run labs. The United Nations' drug czar, Antonio Maria Costa, last month urged Canada to emulate the U.S. and Mexico in cracking down on these precursors, such as over-the-counter cold medicine.

Inspector Doug Ellerker, an assistant director of the Royal Canadian Mounted Police's Drug Branch, said the superlabs are a prime target of RCMP investigators.

"Because of the money to be made, it's a real issue for us to deal with," he said. "We're seeing a turn toward the larger economic-based labs that can produce larger quantities."

Canada's gangs are a multiethnic mosaic -- Quebec biker gangs led by French-Canadians; Chinese- and Vietnamese-led gangs in several major cities. One particular problem, Canadian police say, is extensive infiltration of the trucking industry by criminals whose families emigrated from India.

The National Drug Intelligence Center, in its 2009 report, estimates that Canada-based drug gangs were generating between $33 billion and $56 billion annually from overall drug sales in the United States, with much of the cash smuggled through the Mohawk territory.

"Who knows what this money is funding," Burns said. "We've been fortunate not to have the kind of violence associated with the Southwest border -- knock on wood -- but the potential is certainly there."

In British Columbia, drug-fueled violence already is a serious problem -- blamed for dozens of killings in the past two years, as gangs such as the Red Scorpions and the United Nations battle to profit from two-way trafficking over the border. The main trade pattern: The province's hydroponic marijuana is traded at the border for cocaine, guns and cash.

The cocaine originates mainly in Colombia, comes north into Mexico, then across the U.S., often under the supervision of Mexican traffickers. The marijuana -- renowned for its potency -- fetches a premium price, often $4,000 a pound (a half kilogram) wholesale by the time it reaches Los Angeles, Chicago or New York.

The production of export marijuana and its economic spinoffs have made it British Columbia's third largest industry behind tourism and logging, said criminologist Rob Gordon of Simon Fraser University. "It's a major component of our gross provincial product."

People familiar with British Columbia's marijuana trade have estimated that up to 36,288 kilograms of pot per month is smuggled into the United States, mostly by truck and aircraft.

Smugglers have resorted to imaginative methods. In 2005, police uncovered a 110-metre tunnel running from a home in Washington State to a boarded-up Quonset hut in a Vancouver suburb on the Canadian side.

In April, a British Columbia man pleaded guilty in federal court in Seattle to trying to smuggle more than 771 kilograms of marijuana into the U.S. in the floor of a trailer truck loaded with two-dozen head of cattle. It was not the most pleasant of busts.

"Officers scraped off the natural byproduct of cows and endured the associated odors to unbolt false panels which concealed hundreds of plastic bags of marijuana," according to a U.S. Customs and Border Protection press release.

The smuggling and violence in British Columbia would be alarming at any time, but is especially troubling as the province prepares to host the Winter Olympics next February. Border crossings en route to and from Vancouver will be extra busy, and authorities from both countries want to avoid massive backups while preventing smugglers from capitalizing.

"Security and facilitation go hand in hand," said Alan Bersin, the Obama administration's border czar. He hopes individuals and companies making frequent border crossings will participate in new programs which vet them so they can clear border posts rapidly.

Overall, cross-border teamwork on drug investigations is rated as excellent -- despite occasional logistical challenges such as incompatible radio networks.

"Our cooperation with Canada sets the gold standard for cross-border relations that we seek to emulate with Mexico," Bersin said.

Bersin, whose official title is special representative for border affairs, said the long northern border -- with extensive stretches of wilderness -- requires different policing strategies than the Mexican border.

"Technology necessarily will play a more important role," he said. "You'll want more extensive use of surveillance systems, coupled with communications channels. And partnerships become a very important part of the strategy -- federal, state, local and cross-border."

Last month, the DEA and U.S. Immigration and Customs Enforcement reached an agreement that will enable ICE to assign more of its agents to drug investigations along both borders. "I have no intention of focusing simply on the southern border," said ICE's director, John Morton.

For the Border Patrol, recent initiatives have brought not only hundreds more agents to its northern front, but also new offices and transport, ranging from aircraft and boats to snowmobiles and all-terrain vehicles.

"We patrol mountains, forests, fields -- we need those ATVs," said Mark Henry of the Border Patrol's Swanton Sector, which monitors a 474.7-kilometre stretch of the border from Alexandria, New York, across the tops of Vermont and New Hampshire.

The traffickers "are always probing for a weak point, always trying to get through the woods, down the back roads," Henry said. "They use radios, night vision goggles -- they've gotten more sophisticated."