At least three people were injured, including one seriously, in an explosion in Ukrul town in Manipur on Wednesday, a day before the Republic Day celebrations, police said.
The incident took place at Gandhi Chowk in Imphal in the evening.
Police said they were yet to establish the cause behind the explosion and suspect that the blast could be due to a hand grenade.
Of the three injured, a 49-year-old woman suffered injuries on her stomach and is in critical condition, while the other two are stated to be out of danger, a police officer said.
The injured trio was admitted to Ukhrul district hospital, from where the woman was referred to another medical establishment in Imphal, which is around 3-4 hours away.
The blast created a small crater on the road and caused minor damage to some vehicles parked on the roadside.
No militant outfit has claimed responsibility for the blast so far.