The Chief Executive Member and legislator P N Syiem was suspended by the state party leadership for alleged "anti party activities" last night.
His suspension came as the party prepares to contest for seven vacant posts of the two tribal autonomous district councils.
Following the suspension order, five executive members in the Congress-led People's Democratic Front coalition at the Council tendered their resignation from the party membership and supported Syiem as their leader.
Congress has appointed Mansturdy Nongrem as the new parliamentary party leader in the council.
Syiem, who claimed to have the support of majority of the members at the council, said the appointment of Nongrem was not as per norm since the actual leader did not convene the parliamentary party instead a party functionary did it.