MOSCOW, May 19 (RIA Novosti) - A Tajik national in possession of over 5 kg (11 lbs) of heroin has been detained near Moscow's Kazansky railway station, a police source said on Monday.

"The Interior Ministry's investigation department and transport police detained a Tajik national in possession of 5.2 kg of heroin," the source said.

The Tajik drug market has increased significantly following the withdrawal of Russian border troops from the Tajik-Afghan border in mid-2005.

According to the United Nations Development Program, up to 100 metric tons of heroin is smuggled through Tajikistan annually, enough to meet the annual demand of Europe and North America together.