Iran will completely seal off its eastern borders with Afghanistan and Pakistan by 2015 to prevent drug smuggling and infiltration of armed groups, media quoted the police chief on Saturday as saying. \"About 90 percent of Iran\'s eastern borders have already been sealed,\" Arman newspaper quoted General Esmaeil Ahmadi Moghaddam as saying. \"The remaining 10 percent, in the region of Saravan (near the southeastern border with Pakistan) will be closed within three years,\" he said. \"The border will be sealed even to pedestrians.\" In early 1990, Iran began to build a \"wall\" to seal its approximately 1,800 kilometre-long (1,100 mile) border with its neighbours to control drug trafficking and infiltration of armed rebel groups or bandits. The border \"wall,\" which sometimes consists simply of fencing and barbed wire, is strengthened by a thousand kilometres of embankments, ditches, canals or cement walls. According to official figures, some 3,700 members of Iran\'s security forces have been killed in a three-decade long battle with drug traffickers and armed groups, often equipped with heavy weapons in the restive eastern provinces. Nonetheless, the country is still a main corridor for drug traffickers who smuggle narcotics from Afghanistan -- which the United Nations says produces 90 percent of the world\'s opium -- to the Middle East and Europe. Ahmadi Moghaddam said over the 12 months to March 2011, Tehran seized some 420 tonnes of drugs, or nearly 80 percent of the opium and 40 percent of heroin seized in the world, according to official figures confirmed by the UN Office on Drugs and Crime in Tehran. Iran\'s southeastern province of Sistan-Baluchestan is also regularly infiltrated by armed rebel groups, fuelling chronic insecurity in an area mostly populated by Sunni citizens. Tehran accuses US intelligence and Pakistan of supporting the Sunni extremist group Jundallah (Army of God), which has claimed a series of deadly attacks leaving hundreds dead over the past 10 years in Iranian eastern provinces.