In a letter from the Bulgarian Embassy to Cuba to the Bulgarian Ministry of Foreign Affairs, Deputy Chief of Mission Hubenov writes that confidential archives of the embassy were destroyed at the order of Ambassador Konstantin Michev. Two protocols and a list of demolished materials are referenced in the letter, but not included.

The Bulgarian diplomatic mission (legation or embassy) to the US reported to the Bulgarian Ministry of Foreign Affairs in Sofia what actions the embassy executed and planned to execute to prevent seizure of documents during the "international situation," or Cuban Missile Crisis. Enclosed in the letter is an explanation of items destroyed and items placed under heightened security. The letter also includes information about security for the embassy staff.

The Bulgarian Foreign Ministry sends respects to the Cuban Embassy in Sofia and states that "competent Bulgarian authorities have included the Republic of Cuba as a socialist country in the plan for 1963."

Warning about the content of Castro’s declaration with regard to US threats against Cuba. Reference to the media and other authorities copies of the declaration.