The Congress is now left with just three legislators in the 60-member House.

West Bengal Chief Minister Mamata Banerjee’s Trinamool Congress (TMC) threw a political challenge to ruling CPI(M) in Tripura after six Congress MLAs joined the party on Tuesday. The Congress, which held the position of main opposition party in the State, has also lost another MLA who resigned from the Assembly to rejoin CPI(M).

Multipart political set-up started unfolding since Monday morning after Congress MLA Jiten Sarkar abruptly met Assembly Speaker Ramendra Chandra Debnath to submit his resignation. He later issued a statement announcing his wish to join the CPI(M) — the party he deserted in 2008.

His resignation jolted month-long effort of Congress rebel group, led by former leader of opposition Sudip Roy Barman. Meanwhile, PCC(I) president Birajit Sinha expelled MLA Biwabandhu Sen from the party for six years for alleged breach of party discipline.

It was late Monday night that the rebels urged TMC General Secretary Mukul Roy to reach Agartala by morning flight to complete the joining process. Mr. Barman and three MLAs – Diba Chandra Hrangkhawl, Asish Saha and Biswabandhu Sen — met Speaker Ramendra Chandra Debnath and submitted a letter, also containing signatures of two other MLAs Dilip Sarkar and Pranjit Singha Roy, to appraise their joining to the TMC.

The letter also urged to treat the group as a separate block and declare Sudip Roy Burman as its leader. Mr. Dilip Sarkar could not turn up due to ill health and Mr. Pranjit Singha Roy is away in Bengaluru on medical ground.

Rejuvenated TMC held a big rally in Agartala on Tuesday afternoon raising slogans against Congress-CPI(M) nexus in West Bengal and praising Ms. Mamata Banerjee. Mr. Mukul Roy, who flanked the newly joined leaders in the rally, declared that TMC chief would soon start visiting Tripura to “speedup fight to defeat CPI(M) in 2018 Assembly elections.”

Besides the six MLAs, many former office bearers of the Congress and its frontal organisations joined TMC in the presence of Mr. Mukul Roy. The Congress, which had 10 MLAs, is now left with only three legislators in the sixty-member State Assembly.