"The matter relates to national security and a thorough investigation is required," Mr Singh said while addressing reporters. He also tweeted about the case saying the weapons went missing "during 2014 to 2016 of the previous regime. The case has been handed over to the NIA."
The state government sent the letter to the probe agency on Friday. The weapons were kept at the headquarters of the 2nd Manipur Rifles in Imphal, the capital of Manipur.
In 2016, four persons were arrested and one 9 mm auto pistol and three magazines were seized from them, which could be linked to the missing weapons case from the Arms Kote of 2nd Manipur Rifles, Mr Singh was quoted as saying by news agency PTI.
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