A major share of heroin in South Asian market went to India's local criminal groups, a UN annual drug report said on Thursday.
"In 2009, the total value of the South Asian heroin estimated at $1.9 billion – mostly went to Indian local criminal groups", the World Drug Report 2011 produced by UN Office on Drugs and Crime (UNODC) said.
"With a value of $1.4 billion, the biggest market is in India," it said.
In Asia, the vast majority of heroin consumption occurred in China, Pakistan, the Islamic Republic of Iran and India.
The report said that South Asia was an important consumption and transit point for Afghan heroin in 2009.
The report, however, pointed out that domestically produced heroin and opium is half of the consumption in India.
"Although the majority of users in India use Indian heroin, drug traffickers prefer to export Afghan heroin due to its higher purity," it said.
The report said while opium cultivation in Afghanistan remained stable, the global trend was mainly driven by increases in Myanmar, where cultivation rose by some 20 per cent from 2009.
Consequently, opium production in Myanmar increased from 5 per cent of global production in 2007 to 12 per cent in 2010
Globally, UNODC estimates that, in 2009, between 149 and 272 million people, or 3.3 per cent to 6.1 per cent of the population aged 15-64, used illicit substances at least once in the previous year.
Cannabis is by far the most widely used illicit drug type, consumed by between 125 and 203 million people worldwide in 2009.
"The countries most often identified as sources by the cannabis resin (hash) consumer markets are Morocco, Afghanistan, Lebanon and Nepal/India.
The report found that while global markets for cocaine, heroin and cannabis declined or remained stable, the production and abuse of prescription opioid drugs and new synthetic drugs rose.