HMS L4 and L5 encountered SS Irene after pirates seized her near Hong Kong. The submarines surfaced, challenged the pirate-held ship, and opened fire when it refused to stop. Between roughly six and twelve rounds struck the engine-room area, immobilizing Irene but killing fourteen people, including both pirates and non-pirates. L4, L5, and other Royal Navy vessels then helped rescue about 230 people. Police later identified roughly a dozen suspected pirates among those who reached shore. They were tried and hanged, leaving the episode as an example of both the effectiveness and human cost of submarine counter-piracy patrols.
Chapter · 28:19-30:10
Submarines stop the pirate seizure of SS Irene
Royal Navy L-class submarines used surface gunfire to disable the pirate-held SS Irene and helped rescue most of those aboard.