However, the military influence over the Soviet space program may be the best explanation for this secrecy. The OKB-1 was subordinated under the Ministry of General Machine Building, tasked with the development of intercontinental ballistic missiles, and continued to give its assets random identifiers into the 1960s: "For example, the Vostok spacecraft was referred to as 'object IIF63' while its launch rocket was 'object 8K72K'". Soviet defense factories had been assigned numbers rather than names since 1927. Even these internal codes were obfuscated: in public, employees used a separate code, a set of special post-office numbers, to refer to the factories, institutes, and departments.