A Time magazine article [2] on A.Q. Khan's release from house arrest in Pakistan quoted Joe Cirincione [3], who warned that the Khan nuclear smuggling network may still be functional. Read the article here [2].
Links
[1] https://ploughshares.org/file/300
[2] http://www.time.com/time/world/article/0,8599,1877636,00.html
[3] http://www.ploughshares.org/expert.php?id=103