AGARTALA, February 22: Altogether 17 militants of the Tripura National Security Force, a subsidiary of the outlawed National Liberation Front of Twipra, formally laid down arms this morning. The surrender ceremony was held in front of CRPF inspector-general Vageesh Misra at the CRPF second battalion's headquarters at Narsingarh in Sadar subdivision. The 17 militants, led by Kiranjay Reang, used to work as NLFT collaborators by collecting "tax" and abducting people on a commission basis. They had got in touch with CRPF units in different parts of the state. The CRPF authorities finally rounded them all up for a formal surrender at Narsingarh this morning. The militants deposited three live grenades, three revolvers and seven countrymade guns besides a number of incriminating documents. The well-printed "tax" notices collected from them showed that the Gandacherra block development officer had been asked to pay three per cent of his annual basic salary to the coffers of the militants. Addressing newspersons, Misra said over the past six months the CRPF had lost nearly eight men while fighting the militants but operations were continuing. "For achieving greater success we may make marginal readjustments here and there, but our goal will be to prevent any kind of mischief by the rebels and to put them down," Misra added. He asserted that the forces deployed for counter-insurgency operations here were working in tandem and greater success would follow soon. Hostages freed: Nine railway construction workers kidnapped by the NLFT militants on January 7 returned safely to Dhoomacherra area under Manu police station of Dhalai district yesterday. Director-general of police Bhusan Lal Vohra said they went home shortly after arriving at Dhoomacherra. Police sources said in two successive incidents on January 7, two railway workers - truck driver Venkateswar Rao and his assistant Tapan Mohanty - were abducted from the Nailafapara area under Ambassa police station where they had gone to bring water at 6.30 am. Within two hours, another group of NLFT rebels kidnapped at gunpoint nine railway construction workers employed by a Silchar-based contractor from Sindukumar para under Manu police station. They were Prasenjit De, Nihar Ranjan Das, Chandrasekhar Mal, Biplab Das, Saumitra Chowdhury, Rameswar Baidya, Harendra Singh, junior engineer Narayan Deori and another unidentified person. Within four days of their abduction, Venkateswar Rao and Tapan Mohanty returned safely from militant custody but the nine others remained. The police and paramilitary forces in Dhalai district launched a massive combing operation under the leadership of Dhalai superintendent of police Kshatrajay Reang and effectively confined the abductors and the captives within the state. Inspector-general of police (law and order) K. Salim Ali said, "They suddenly surfaced in Dhoomacherra area and I do not think any big amount of ransom had to be paid for their release by the contractor." Ali said the hostages had remained within the state. Vohra expressed satisfaction over the safe return of the railway construction workers. In a separate incident, security forces last night recovered three skeletons of Oil and Natural Gas Corporation workers, abducted by militants last year. Police sources today said following confessions by an arrested militant, three skeletons were recovered from a jungle at Shyamnagar under Takarjala police station area in West Tripura district. The victims, along with nine other ONGC workers, were abducted by tribal guerrillas on March 19 last year from a drilling site in Takarjala area. Two of them, however, managed to escape while others were untraced. The police recovered seven skeletons from the area on January 13 and February 19 following a statement by one Jawahar Lal Debbarma.