Since its establishment in 1976, the ONCB has been reorganized several times. At present, by virtue of the Article 8i of Administration Organization of the State Act B.E. 2534 (1991), as amended by Administration Organization of the State Act (No.4) B.E. 2543 (2000), Minister of Justice has issued the Ministerial Regulation, as announced in the Royal Gazette dated March 10, 2548 (2005) to reorganize the ONCB as follows:
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