Singh was arrested on May 5 after it came to light that eight Assam Rifles personnel had allegedly waylaid a SUV on the night of December 14 last year near the southern outskirts of Aizawl and decamped with 52 gold bars worth around Rs 14.5 crore, a mobile phone and Rs 75,000 in cash after threatening the driver of the vehicle, Lalnunfela, at gun point.
Other accused in the case - four civilians and eight Assam Rifles personnel have been remanded to judicial custody.
Both Mathipi and Baid were released on bail on May 13.