permanent blocking

This was blocking that could be required for all foreigners (excluding citizens of the USSR, Hungary, Bulgaria,East Germany, Poland, Cuba) and homeless people with permanent residence outside Czechoslovakia. Permanent blocking was done only upon arrival in the Czechoslovakia. The condition was that the person in question was working in one of the operative files. Departures of foreigners from Czechoslovakia were blocked once. The permanent blocking always lasted until the end of the calendar year in which it was introduced and renewal was possible by written request at the Central Operations Center (ÚOS CENTRE) until 15 December of the year in which the blocking took place.

Also see: blocked person, blocking of persons of interest, one-time blocking