Section 6 in The North-Eastern Areas (Reorganisation) Act, 1971
6. Formation of the Union territory of Mizoram.
On and from the appointed [day] [i.e. 21-1-1972] there shall be formed a new Union territory, to be known as the Union territory of Mizoram, comprising the territories which immediately before that day were comprised in the Mizo District in the existing State of Assam and thereupon the said territories shall cease to form part of the existing State of Assam.
