The 60-member Tripura Assembly goes to the polls on February 18 and the BJP and the IPFT have entered into an understanding, whereby the former will field candidates from 51 seats and the latter from nine.
"I would appeal to you all to remain alert about their conspiracy, keep a close vigil on the situation and inform the police if you find outsiders moving around your locality," Sarkar told an election rally here.
Sarkar, who is a CPI(M) politburo member, said the BJP had raised a slogan of changing the government in Tripura, but the people of the country were preparing to change them in the 2019 Lok Sabha polls for their "jumla" or the promises they failed to honour.
He added that the people of the state had witnessed the days of insurgency and were now being organised under the Left flag to give a befitting reply to the BJP-IPFT alliance.
Referring to the IPFT's call for a separate state by carving out the Tripura Tribal Areas Autonomous District Council (TTAADC), the veteran CPI(M) leader expressed confidence that the people of the state would not let that happen and that they would protect the state by all means.