Russia’s Yasen-class submarine is one of the most advanced attack submarines in its fleet, built for modern naval warfare.

Submarines have quietly become some of the most powerful weapons in modern naval warfare.

Ukraine's internal security agency said it used an underwater drone to damage a Russian submarine. The agency described the attack as a first, potentially signaling a new chapter in drone warfare.

Add Yahoo as a preferred source to see more of our stories on Google. President Volodymyr Zelensky of Ukraine visits the White House on Oct. 17. On Monday, the Ukrainian Security Service announced it ...

Ukraine’s Security Service said it had disabled a Russian Kilo class submarine in a rare underwater drone attack in the Black Sea port of Novorossiysk. Russia denied any damage from the attack, saying ...