The militants hurled the grenade at the All Minority Students Union office at Bagorgaon village under Bijni police station at around 8.45 AM, official sources said.
The anti-talk National Democratic Front of Bodoland (NDFB-S) faction triggered the blast this morning.
On the eve of Independence Day (Aug 14), two blasts were triggered by the National Democratic Front of Bodoland (S).
One of the explosions took place near a gas agency at Batabori near Bijn town last night.
While, another grenade blast took place at a separate place. No one was injured in the two explosions.
However, in a separate incident, one person was injured in serial blasts near the venue of the Independence Day function in Assam's Kokrajhar district.