Guwahati,   Security forces in Assam, in association with their counterparts in Nagaland, have launched a massive search operation to locate the three ONGC employees who were abducted by suspected ULFA-I militants in eastern Assam's Sivasagar on Wednesday.

Assam's Special Director General of Police, Law and Order, G.P. Singh is camping at Lakuwa in Sivasagar district to supervise the operations to locate the hostages.

Police officials in Sivasagar said that the terrorists of the outlawed United Liberation Front of Asom-Independent (ULFA-I) are likely to go to Myanmar with the captives via Mon district in northern Nagaland.

The Assam Rifles, which is guarding the Myanmar border, has been asked to intensify their vigil along the forested borders.

Sivasagar's Superintendent of Police Amitava Sinha said that the incident was reported early on Wednesday. He told the media that all the security forces in Assam bordering Nagaland along with the security forces of the neighbouring state are conducting massive search operations to locate the staffers of the Oil and Natural Gas Corporation.

The three kidnapped employees are Mohini Mohan Gogoi, a junior technician, production, from Sivasagar district, Alokesh Saikia, an assistant junior engineer, production, from Jorhat district and Ritul Saikia, also an assistant junior engineer, production, from Golaghat district.

An ONGC statement said that the abduction took place from a rig site of the company in Lakuwa field of Sivasagar, and the abducted employees were taken away in an ambulance vehicle belonging to ONGC. Later, the vehicle was found abandoned near the Nimonagarh jungles close to the Assam-Nagaland border.

A complaint has been lodged by ONGC with the local police.

Strongly condemning the abduction of the ONGC employees, Assam Chief Minister Sarbananda Sonowal, in a tweet, said that he has asked Chief Secretary Jishnu Barua and DGP, Bhaskarjyoti Mahanta to take all possible measures for their release.

ONGC has been exploring and producing oil and gas in eastern Assam since the early 1960s.

The outlawed ULFA-I, headed by self-styled commander-in-chief Paresh Barua, had recently released radio operator Ram Kumar, a resident of Bihar, and drilling superintendent Pranab Kumar Gogoi of Sivasagar district, over more than 100 days after the two employees of Delhi-based private oil and gas exploration company Quippo Oil and Gas Infrastructure Ltd were abducted from Arunachal Pradesh on December 21 last year.