In October 2024, China exposed the deployment of covert underwater deep-sea spying devices—dubbed 'underwater lighthouses'—by foreign adversaries near its territorial waters. These sophisticated systems, disguised as scientific research equipment, were actively monitoring naval movements, gathering classified maritime intelligence, and potentially guiding espionage operations. The breach compromises China’s strategic military positioning, undermines maritime sovereignty, and escalates geopolitical tensions in the Asia-Pacific region.The infiltration threatens national security protocols, as the stolen data could include submarine routes, fleet deployments, and underwater communication networks. Given the devices’ proximity to disputed zones (e.g., the South China Sea), the incident risks exacerbating territorial conflicts and could provoke retaliatory cyber or kinetic responses. The Chinese government has demanded counterespionage measures, but the long-term damage includes eroded trust in maritime research collaborations, increased militarization of the region, and the potential for asymmetric warfare tactics (e.g., sabotage of critical underwater infrastructure). The attack’s scale and targeting of state-level defense assets align with high-stakes cyber-physical threats.