Thanks to the publication of an extensive report from the Committee on North Korean Human Rights on the subject of North Korean abductions, there is an excellent conversation going on at the indespensible blog for North Korean-China issues, One Free Korea, regarding the nature and the veracity of allegations that China allows North Korean agents into the PRC to hunt down and abduct people who are judged to be enemies of the DPRK.
The committee’s report, cited below and at at One Free Korea, asserts that North Korea has abducted about 200 people from China in the last twelve years or so.
See: Yoshi Yamamoto, Taken! North Korea’s Criminal Abduction of Citizens of Other Countries (Committee on North Korean Human Rights, May 2011) http://www.piie.com/blogs/TAKEN-Final-Proof.pdf
See Also
Mike Kim, Escaping North Korea (Rowman & Littlefield, 2008), pp. 33-35.
Adam Cathcart, “Allegations of Rogue North Korean Agents in Chinese Border Region, Sinologistical Violoncellist, 31 August 2009, https://adamcathcart.wordpress.com/2009/08/31/allegations-of-rogue-north-korean-agents-in-chinese-border-region/
Adam Cathcart, “Fistfuls of Chinese Earth, Breaths of Conspiracy, Fusillades of Propaganda,” Sinologistical Violoncellist, 3 September 2009, https://adamcathcart.wordpress.com/2009/09/03/fistfuls-of-chinese-earth-breaths-of-conspiracy-fusillades-of-propaganda/
Joshua Stanton, “For North Korean Spies, Sending Refugees to the Gulag is Entry Level Work,” One Free Korea, 19 April 2010 http://www.freekorea.us/2010/04/19/for-north-korean-spies-sending-refugees-to-the-gulag-is-entry-level-work/
Joshua Stanton, “Ten Years Later, South Korea Questions North Korean Agent in U.S. Resident’s Kidnapping,” One Free Korea, 16 January 2010 http://www.freekorea.us/2010/01/16/ten-years-later-south-korea-questions-suspected-north-korean-agent-in-us-residents-kidnapping/
Chosun Ilbo, “North Korean Abduction Squad Roams Freely Through China,” January 19, 2005 http://english.chosun.com/site/data/html_dir/2005/01/19/2005011961043.html
Chosun Ilbo, “Ethnic Korean ‘Mole’ Helped N.K. Agents Abduct Pastor in China,” 14 December 2004 http://english.chosun.com/site/data/html_dir/2004/12/14/2004121461025.html
Chosun Ilbo Editorial, “N.K. Should Avoid Provocation and Return Kim,” 14 December 2011 http://english.chosun.com/site/data/html_dir/2004/12/14/2004121461036.html
Chosun Ilbo, “N.K. Abducted 40 from 1999 to 2001,” Jan. 19 2005 http://english.chosun.com/site/data/html_dir/2005/01/19/2005011961017.html
Chosun Ilbo, “Beijing Turns Blind Eye to North Korean Kidnappings,” 19 January 2005 http://english.chosun.com/site/data/html_dir/2005/01/19/2005011961031.html
Huanqiu Shibao [Global Times, Beijing], “韩国派特工在中国调查电话诈骗案/Hanguo pai tegong zai Zhongguo diaocha dianhua zapian an [The Incident of South Korea Sending Spies to China to Investigate Telephone Blackmail],” http://world.huanqiu.com/roll/2009-09/564229.html
Lee Hae Young, Lives for Sale: Personal Accounts of Women Fleeing North Korea for China, U.S. Committee for Human Rights in North Korea, 2009 http://www.hrnk.org/download/Lives_for_Sale.pdf
Adam Cathcart 
Many thanks, Adam, for putting these sources together.
As some of us used to say: Venceremos! And indeed, No pasaran!
(Always good to liberate a slogan from its originators…)
Thank you, Aidan. Hopefully, every so often I am able to get outside of the confines of what one skilled writer calls “fashionable American-style braggadocio” and get some decent content out there for sharp colleagues such as yourself. I appreciate your endorsement of my recent work, although, like the New York Philharmonic’s visit to Pyongyang, the challenge is to take the transitory apparent success and render it permanent. One performance does not a monument make, and the Juche tower doesn’t build itself. So much easier said than done, in my case! Cheers.