Agartala, Jan 22 : Tripura police busted a nexus of monetary transactions between the militants and the contractors, and arrested four persons, police said on Thursday. A senior police officer said that the police and Tripura State Rifles (TSR) troopers, acting on an intelligence report on Wednesday, arrested four persons hours before the transaction of Rs 15 lakh to the banned National Liberation Front of Tripura (NLFT) extremists. "A team of police and TSR personnel led by sub-inspector Ajit Debbarma of Raishyabari police station under Dhalai district (in eastern Tripura) arrested the three persons along with Rs 15 lakh hours before they handing over the money to the NLFT rebels. Police arrested the three people and following their confession arrested an NLFT collaborator, who was hiding in a nearby areas," the official said. An official statement, issued by the police headquarters said that during investigation and from the source information, it was revealed that some of the construction agencies instead of taking police help are assisting the extremists group by providing money clandestinely. "In course of investigation of the recent militants' abduction of three persons, it was transpired that an NLFT extremist group with sophisticated arms led by Bikram Bahadur Jamatia was camping in Bangladesh, opposite to eastern Tripura's Raishyabari border. The militant group was engaged in extortion of money from the construction agency which constructed the border fencing along the India-Bangladesh border along Tripura," the statement said. The NLFT extremists had earlier on December 23 released three persons after 17 days of captivity. Supervisor Subhash Bhowmik, 48, JCB driver Subal Debnath, 37, and worker Gana Mohan Tripura, 37, were kidnapped by the NLFT ultras from Malda Kumar Para in eastern Tripura's Dhalai district on December 7 while they were engaged in border fencing work along the international border. The NLFT militants had whisked away the three hostages to Bangladesh since the crime spot was just along the international border. The government-owned National Building Construction Corporation was assigned the task to put up a barbed wire fence along the India-Bangladesh border to check crimes and infiltration. Meanwhile, the Tripura police on January 15 recovered the mutilated body of a trader 50 days after he was kidnapped at gunpoint by terrorists from the northern part of the state. Inspector General of Police (Law and Order) Arindam Nath told IANS that the slain Litan Nath's body was recovered by the police from a forest in the Khedachara area in North Tripura district. Earlier the state police, Tripura State Rifles and central para-military forces had jointly launched a massive combing operation to rescue the trader and also detained four suspected NLFT militants from the areas adjoining Mizoram and Bangladesh. Litan Nath's wife told the police that a few heavily armed militants had raided their house on November 27 and looted jewellery, cash and abducted her husband. After several years of lull, of late terrorist activities have resurfaced in Tripura, which was until 2008-09 devastated by the decades old insurgency. /IANS