A second senior leader of a vast drug syndicate has been arrested, a Thai narcotics official said, as a transnational dragnet tightens on the Sam Gor group, which police say dominates the US$70 billion annual Asia-Pacific drug trade.

The October arrest of Hong Kong citizen Lee Chung Chak in Bangkok preceded last month’s high-profile arrest in the Netherlands of Tse Chi Lop, a China-born Canadian national who police suspect is the top leader of the syndicate, also called “The Company”.