They say a tip led the officers to begin searching on Wednesday.
They found 14 weapons – prompting the lockdown, according to the New York State Correctional Officers and Police Benevolent Association.
Ultimately, they found 52 weapons on Wednesday and 38 on Thursday.
State corrections confirmed that the facility was placed on lockdown after an increase in the number of contraband weapons.
They said the prison would remain locked down for several more days.
The state said such lockdowns are routine and they enable staff to search for contraband.
Union officials say the development reflects an increase in danger for prison officers:
"Assaults on staff at the end of 2013 were at a five year high and inmate on inmate violence had increased by 17 percent in the past year. This coincides with four more prisons being closed in 2014, creating additional overcrowding as well as more violent felons being housed in medium security facilities," the union said in a statement regarding the lockdown.
The state declined to address the union's claims. But confirmed that the prison is in a lockdown after finding an increase of contraband weapons.
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