On 4 August 2023, the Russian merchant tanker (MT) Sig was attacked and disabled near the Kerch Strait, apparently by an Uncrewed Surface Vessel (USV). This came a day after a similar attack on the Olenegorsky Gornyak landing ship, and two days after an apparently foiled attack on Russian patrol boats while they were likely escorting the Russian merchant vessel (MV) Sparta IV.

Although civilian-flagged, MT Sig and MV Sparta IV have long been contracted to ship fuel and military supplies between Russia and Syria. Since 28 February 2022, Russian military ships have not been able to pass through the Bosphorus, leaving Russian military forces in Syria and the Mediterranean heavily dependent upon Sig, Sparta IV, and a handful of other civilian vessels.

The attacks show that USV operations are increasingly a major component of modern naval warfare and can be turned against the weakest links of Russia’s sea supply lanes.