The recovered arms and ammunition were suspected to be hidden by the proscribed outfit Garo National Liberation Army (GNLA).
They were recovered from the jungle of Pilgonggre area under Williamnagar police station.
According to a senior police official in the East Garo Hills district, an operation was launched in the Pillongre area of the Durama range on Saturday.
"On early Saturday, around 1:40 am, the operation team recovered a huge cache of arms ammunitions from Pillongre area which are suspected to have been hidden by GNLA Commander-in-Chief Sohan D Shira who had died in police action," the police official said.
The police team recovered 79 rounds of Anti Aircraft live ammunition, 175 rounds of 7.7 live ammunition, 10 numbers of Electrical Detonators, one 12-bore Double Barrel and approximately 250 grams of Gelatin from the area.