Assam's Bodoland People's Front (BPF) moved the Supreme Court on Sunday seeking postponement of polling in Tamulpur, after its candidate - Rangja Khungur Basumatary - defected to the BJP less than a week before voting and after the deadline for withdrawal of nominations.
Tamulpur, which is in Baksa district under the Bodoland Territorial Region, votes on Tuesday - the third and final phase of the Assam Assembly election.
BPF chief Hagrama Mohilary has already written to the Election Commission - twice - to ask for polling to be suspended and for permission to change his party's candidate for the seat.
"Since the candidate nominated by my party has changed his political allegiance barely a few days before polling through illegal inducements including bribery, he is no longer entitled to receive the votes under the BPF symbol," Mr Mohilary said on Friday, calling Mr Basumatary's decision to join the BJP an "act of fraud" that violated the "core requirement of fairness in elections".
A day earlier Mr Mohilary wrote to request that polling be cancelled and that an FIR (first information report) be filed against Assam minister Himanta Biswa Sarma and Union Minister Narendra Singh Tomar, who were present as Mr Basumatary joined the BJP.
BJP chief JP Nadda, Assam Chief Minister Sarbananda Sonowal and Assam BJP chief Ranjeet Kumar Dass were also named - for allegedly luring Mr Basumatary in a "fraudulent manner".
News of Mr Basumatary's defection to the BJP also prompted a furious backlash from the Congress, for whom MP Manish Tiwari accused the BJP of threatening him, and slammed the party's "fascist mentality". "You (BJP) want to win the poll by wrong means," he said.
The Congress has also joined the BPF in calling for polling to be suspended.
State chief Ripun Bora also called for action against BJP leader and minister Himanta Biswa Sarma, for having met Mr Basumatary before he switched over.
According to news agency PTI, the Election Commission heard the matter on Saturday. Sources told PTI no decision has been announced so far.
A local TV channel had reported that Mr Basumatary, believed to be missing for around 48 hours before he joined the BJP on Thursday, said he quit the BPF over a lack of help during campaigning.
The Bodoland People's Front was once an ally of the BJP.
Mr Mohilary's party switched to the Congress in February - after the BJP dumped it to ally with the United People's Party Liberal (UPPL) to form the Bodoland Territorial Council last December.
The results of the Assam Assembly election are expected on May 2.
With input from PTI
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