The official Iranian news agency says the smugglers were moving drugs and weapons from the Sistan-Baluchistan province near Iran's border with Afghanistan and Pakistan, to markets in Turkey and Europe.

Iran is a major smuggling route for traffickers peddling drugs produced in Afghanistan and Pakistan for sale in Europe and Gulf Arab states.

Crackdown

Last week, police seized four tonnes of opium during clashes in which several traffickers were reported to have died in south-eastern Kerman province.

It was the largest haul in the history of the province.

This is the third major drugs seizure this month

A police commander said the traffickers were also attempting to smuggle arms and other drugs in three cars, one of which was destroyed in a shoot-out.

Earlier in the month police killed a smuggler and seized 750 kg (1,650 lb) of opium and heroin in neighbouring Yazdi province.

Iran has stepped up operations against drug smugglers, spending nearly $20m in 2000 in the fight against narcotics.

Police recovered 180 tonnes of opium that year, accounting for 85% of the world's drug seizures.