Two undersea internet cables in the Baltic Sea have been disrupted, with one cable between Lithuania and Sweden being cut and another cable linking Finland and Germany also experiencing a fault. The cause of the disruptions is unclear, but there are concerns about possible Russian interference with global undersea infrastructure. The US has detected an increase in Russian military activity around deep sea telecommunications cables, and there are warnings of possible 'hybrid warfare'. Repairs are underway, but the extent of the disruption and its impact are still being assessed.