Region: Semi-submersibles new tactic in drug trafficking across Pacific

Between 28 July and 5 August, semi-submersible vessels were discovered washed ashore in Tonga and the Solomon Islands. According to the Head of the Pacific Regional Security Hub at Canterbury University, Jose Sousa-Santos, drug cartels are using Pacific Island countries as transit or refuelling points en route to Australia and New Zealand. Sousa-Santos assessed that drug cartels target the lack of radar technology to detect low-profile vehicles, and the overall limited regional law enforcement capacity.

Assessment: Semi-submersible vessels are a new tactic for drug cartels. The interception of a private yacht by the French Navy in the Marquesas in mid-July demonstrates that semi-submersibles are one of several methods used in the region. Officials from Fiji and Samoa have stated that their countries have become a market for transnational drug cartels, illustrating that Pacific Islands are not only a transit point. Both the quantity of drugs and tactics for trafficking are likely to increase while maritime domain awareness, information sharing, and institutional knowledge of transnational organised crime remain limited amongst Pacific states.

Sources: Margot Staunton, “Narco-sub threat: Expert warns drug cartels using 'new trend' to target the Pacific,” RNZ, August 20, 2025; Kalino Latu, “Silent invaders: Tonga faces new drug smuggling tactics as narco-subs emerge in the Pacific,” Kavina Tonga, August 4, 2025; Gina Maka’a, Dan McGarry, “Mystery Deepens as Second Narco-Sub Washes Ashore in Solomon Islands,” OCCRP, August 21, 2025.