Four explosions put Upper Assam Division in India on the edge on Sunday morning, as the country celebrated its 71st Republic Day, NDTV reported.
All four blasts took place in a span of 10 minutes between 8:15 and 8:25 am, a police officer said.
There were no reports of any deaths. Republic Day being a holiday, people were mostly indoors, he said.
CCTV footage showed two young men on a motorcycle throwing a grenade and speeding away, the officer said.
According to sources, the explosions were suspected to be carried out by the ULFA (Independent) militant group.
The ULFA (I), along with several other such outfits in the Northeast, had called for a boycott of Republic Day celebrations.