73-years-old and mentally unstable, Saikhom Ramo Singh of Khurai Sajor Leikai in Imphal east district was arrested on the charge of killing his mother on October 7, 1982, officials said.
Initially he was put in Manipur Central Jail in the heart of the town and later transferred to Sajiwa jail in the outskirts.
His younger brother and grand nephews received Ramo Singh on his release last evening, family sources said.