The Russian cargo ship Ursa Major sank in December 2024 near Spain after suffering three explosions, raising significant security concerns globally. The vessel, which had previously supported Russian military operations, was reportedly carrying components for nuclear reactors, potentially bound for North Korea. Investigators are exploring theories of sabotage, including the possibility of a supercavitating torpedo or a limpet mine causing damage to the hull. Despite the suspicious circumstances, no country has taken responsibility for the incident, and NATO's involvement remains unverified. The Spanish investigation revealed that the ship was tracked by military vessels and aircraft before its sinking. Following the incident, US WC-135 aircraft, known for detecting nuclear debris, flew over the wreck area, although no findings were disclosed. The mystery surrounding the Ursa Major's sinking continues, with limited information released by governments and ongoing questions about the ship's cargo and the circumstances leading to its demise.