TEHRAN, Aug 4 (Reuters) - Iran has arrested a major international drug trafficker, state television reported on Saturday, saying he had smuggled dozens of tonnes of narcotics into the Islamic state each year.

Iran, which forms part of a major drug smuggling route, shares a 900 km (560 mile) border with Afghanistan, the world's number one producer of the opium poppy which is the key ingredient for heroin.

"He was bringing 50 tonnes of narcotics into the country every year and was transiting a part of it to other Gulf countries and Turkey," the television said, adding that he was arrested while selling a large amount of drugs in Tehran.

The man, identified as Jom'eh Khan Gomshad Zehi, was also accused of involvement in killing nine police officers, it said, adding that he used to live in Iran close to the Pakistani border but had been on the run in Afghanistan for several years.

State television said Gomshad Zehi was on a United Nations list of major drug traffickers, but did not give details.

Iranian forces often clash with well-armed drug smugglers in remote eastern regions near Afghanistan and Pakistan, an area dotted with forts, trenches and machinegun posts.

More than 3,300 Iranian security personnel have died fighting drug traffickers since the 1979 Islamic revolution. Iran, Afghanistan and Pakistan agreed in June to launch a joint crackdown on drug trafficking.

Crimes such as drug trafficking and murder are punishable by death in Iran.

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