The guerrillas, led by their self-styled corporal Bisurai Debbarma, 33, surrendered on Thursday night, Tripura Police spokesman Uttam Kumar Bhowmik said.
"The tribal extremists fled from their clandestine camp at Thangnang (under Rangamati district of Chittagong Hill Tract of southeast Bangladesh) and crossed over to India on Wednesday night," said Superintendent of police (Special Branch) Arindam Nath, to whom the rebels surrendered.
They also deposited some electronic gadgets and incriminating documents with the police.
Aged between 27 and 33, the militants told the police that they fled from the NLFT camp in Bangladesh out of frustration and miserable conditions.
According to them, more NLFT cadres from Bangladesh are likely to surrender.
Banned in 1997 by the Union Home Ministry, the two outfits have sought secession of Tripura from India.
ATTF has become almost defunct due to the surrender of most of its cadres.
A senior police official, citing intelligence reports, said that the Bangladesh Army and security forces in separate operations have recently busted two camps of the NLFT and National Socialist Council of Nagaland (Isak-Muivah faction) in mountainous Chittagong Hill Tracts.
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