At least 11 civilians have been gunned down by security forces in Nagaland's Mon district, police said on Sunday, adding that it is investigating whether the incident was a case of mistaken identity.
The exact number of fatalities, however, is yet to be ascertained as 11 people died on the spot, and several others succumbed to their injuries in hospitals in neighbouring Assam, a police officer said.
Chief Minister Neiphiu Rio promised a high-level probe into the incident and appealed to all sections of the society to maintain peace.
The incident took place between Oting and Tiru villages when some daily-wage labourers were returning home in a pick-up van from a coal mine on Saturday evening, the police officer said.
The vehicle was allegedly fired upon by Army personnel, who were conducting an operation in the area after receiving inputs on the movement of militants of Yung Aung faction of proscribed outfit NSCN (K), he said.
An investigation is underway to ascertain whether the incident was a case of mistaken identity, the officer said.
Mon shares a porous international border with Myanmar, where the Yung Aung faction of NSCN (K) is based.
The situation is under control and police is conducting spot verification, he said.
Chief Minister Neiphiu Rio condemned the incident and assured that it will be investigated.
"The unfortunate incident leading to killing of civilians at Oting, Mon is highly condemnable. Condolences to the bereaved families & speedy recovery of those injured. High level SIT will investigate & justice delivered as per the law of the land. Appeal for peace from all sections," he tweeted.
Deputy Chief Minister Yanthungo Patton promised that justice will be delivered.
"Oting's (Mon) disturbing and tragic incident in which civilians were killed will be thoroughly investigated and justice will be served. Condolences to the bereaved families and prayers for the speedy recovery of the injured. In the wake of the tragedy, I urge peace from everyone!" he tweeted.
Though the Army is yet to issue a statement, Assam Rifles has denied its involvement in the incident.