By Fredrik Dahl TEHRAN, May 13 (Reuters) - Iran is stepping up its fight against drug smugglers, spending hundreds of millions of dollars to build an "Iranian wall" along its remote border with Afghanistan and Pakistan, a U.N. official said on Sunday. Iran is a main transit route for bringing heroin and opium to Western markets from Asia, but the United Nations' top anti-drugs official in Tehran praised the country for its efforts in stopping traffickers and seizing narcotics. Seeking to stem the flow of drugs, the Islamic Republic is expanding work to erect big earth and stone embankments and dig deep ditches covering hundreds of kilometres (miles) of its eastern frontier. The border region is also dotted with police observation towers and fortress-style garrisons for troops combating heavily armed gangs of smugglers. "Definitely drug control is one of the positive stories (from Iran)," said Roberto Arbitrio, representative of the United Nations Office on Drugs and Crime (UNODC). "This is the first country in the world in terms of opiate seizures," he told Reuters in an interview, referring to opium, morphine and heroin. "Last year it was 300 tonnes." Iran shares a 900 km border with Afghanistan, where opium production has soared since the 2001 downfall of the Taliban, and has come under increased pressure from criminal groups seeking to take their lucrative trade to the West. Afghanistan is the world's number one producer of opium poppy, the key ingredient for heroin. Opium production rose as much as 50 percent last year to supply more than 90 percent of global heroin, according to a United Nations estimate. But Iran, where an estimated 1.2 to 2 million people use narcotics, is striking back in what Arbitrio described as a "war" on drugs. Thousands of police and soldiers have been killed in drug-related operations since Iran's 1979 Islamic revolution. "Every week you have one or two police killed," he said. In the 1990s, Iran began to construct physical barriers to make it more difficult to transport narcotics into the country and is now adding hundreds of kilometres to link the different sections to each other, as far as the rough terrain allows. "If you go the border there is what we call the Iranian wall ... against drugs," Arbitrio said. "Large parts have already been built. I've never seen something like this, it is outstanding." He said Iran's campaign was showing results with the country seizing an estimated 20-40 percent of trafficked volumes, as compared to 5-10 percent in the United States and Europe. "So they are doing extremely well," Arbitrio said. "Of course this will not stop 100 percent the trafficking but it will make traffickers' lives more difficult."
