Police officers catch a foreign drug dealer in a campaign in Sanlitun, Chaoyang District, Beijing,May 24.[Photo/IC]

Beijing police said on Monday that they have cracked down since February on a series of foreign drug-dealing gangs and arrested more than 30 foreign dealers in a campaign to strike drug trafficking by foreigners in the capital, chinanews.com reported.

One of the arrested was found carrying students' IDs from universities in Beijing and another was carrying a UN refugee certificate, along with parcels of marijuana, meth and MDMA.

According to the police, the foreign drug dealers smuggled drugs from southern China, and they formed a circle of trading based in the Sanlitun and Dongba areas in Beijing's Chaoyang district.

They sold drugs to so-called familiar customers, as well as new ones through introduction, sometimes via WeChat, an instant messaging service, to avoid the risk of being caught.

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