Mr Lyngdoh is a minister in Chief Minister Mukul Sangma's cabinet.
Mr Lapang will be an adviser to the state unit. Mr Gandhi appointed Vincent H Pala the working president of the Meghalaya Pradesh Congress Committee.
He formed a 13-member pradesh election committee under Mr Lyngdoh, with Mukul Sangma as a member. The state goes to polls early next year.
Mr Gandhi also formed an election committee, campaign committee and media committee of the Nagaland Pradesh Congress in view of elections in the state, AICC general secretary Janardan Dwivedi said in a statement.
K Therie will be the chairman of the election committee for Nagaland. Ayangba Aonok will head the campaign committee, while Captain GK Zhimomi will lead the media committee.
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