The blast took place at a pipeline of Oil India Limited at Dikom in Dibrugarh district. Dikam is located about 80 km away from the Dhala-Sadiya bridge, which will be inaugurated by PM Modi on Friday. It will connect Assam with Arunachal Pradesh.
While the police claimed that the blast took place due to pressure in a pipeline and that there was no involvement of any militants, the anti-talk faction of ULFA terrorists reportedly claimed responsibility for the explosion.
Assam's Special Director General of Police (DGP) Kula Saikia refuted the ULFA faction's claim.
"We suspect that the explosion took place due to pressure in the pipeline. However, our investigation is on," Mr Saikia said.
The anti-talk faction, however, told a news channel from Assam that they had triggered the blast and added that one of their cadre, Bobby Dahotiya, was killed while planting the bomb on the pipeline.
Security has been intensified.
Additional Director General of Police (Special Branch) Pallab Bhattacharyya had earlier said that they had received intelligence inputs that a group of Myanmar-trained ULFA cadres had entered the state ahead of the scheduled visit of the Prime Minister.