Group 1 - The UK Ministry of Defence has acknowledged a "serious nuclear incident" at the Faslane naval base in Scotland, classified as an "A-class incident," indicating a significant risk of radioactive material leakage into the environment [1][3] - Concerns have been raised regarding the safety of the maintenance of the Trident submarines at the base, as well as the transparency of information related to the incident [3] - The incident occurred between January and April of this year, but the Ministry of Defence has not disclosed specific details or confirmed whether there was any actual radiation leakage [3] Group 2 - This is not the first "A-class incident" reported at the Faslane naval base; previous incidents were reported between 2006 and 2007, and a similar event occurred in 2023 [3] - The Faslane naval base serves as the home port for the UK's submarines, including the Vanguard-class nuclear submarines equipped with Trident missiles [3]