Lawngtlai deputy commissioner administered oath of office and secrecy to Chinzah.
Lallawmsanga Apetow, who was appointed as protem chairman, also took oath in the swear-in ceremony held at the council secretariat.
The protem chairman administered the oath of affirmation to the other newly elected members.
Speaking on the occasion, Manghmunga Chinzah said he will ensure that a transparent Government is being set up in the LADC.
He said that his government would make massive efforts to usher in development in the LADC area.
He also sought cooperation from the people and staff of the council to expedite the development process in the council area.
Senior politician in the Lai area, Chinzah has been elected as a member of LADC for seven times.
The new CEM assumed office on Monday.
In the LADC polls held on December 4, the ruling MNF got the majority by winning 20 out of 25 seats, while BJP and Congress bagged one seat each and three independent candidates were also elected.