The photographs clearly revealed that the youth, Chongkham Sanjit, was taken inside a pharmacy by security forces in capital Imphal unchallenged and then his dead body was brought out.

'We want the chief minister's resignation as well as a judicial enquiry into the entire incident,' said Radhabinod Koijam, former chief minster and leader of the opposition Nationalist Congress Party.

'Extra judicial killings by security forces in Manipur have assumed alarming proportions. The case of Chongkham Sanjit is another example of fake encounters,' Suhas Chakma, chairman of the Asian Centre for Human Rights, told IANS.

The state government maintains the Sanjit was killed in a gunfight.

'We shall inquire into the matter,' Chief Minister Okram Ibobi Singh said.

There are an estimated 19 rebel groups active in Manipur, bordering Myanmar, with more than 10,000 people killed in the last two decades of insurgency in the state.