22 December 2021
Major Jeffrey A. VanAuken
Troop C Commander


Update: The Trooper who fired his division-issued firearm in Wednesday’s officer-involved shooting in Unadilla is identified as Trooper Justin Miller.

Trooper Miller is assigned to SP Sidney and has been a member of the New York State Police since 2016.

Update:  On December 22, 2021, shortly after 7:00 p.m., New York State Police at Sidney were dispatched to a report of a domestic dispute at a residence on Lyons Street in the village of Unadilla. 

The responding trooper was confronted by Mark A. Beilby, age 24, who was armed with a knife inside the home.  Beilby did not comply with the trooper’s repeated commands to drop the knife and advanced at the trooper.  The trooper discharged his issued firearm, striking Beilby. 

Beilby was transported to Tri-Town Hospital then transferred to Wilson Medical Center where he was pronounced deceased. 

The New York State Attorney General’s Office is investigating the incident pursuant to Executive Law Section 70-b in conjunction with the New York State Police.    


Original Release: State Police investigating an officer involved shooting in Unadilla 

On December 22, 2021, at around 7:20 pm, State Police responded to Lyons Street in the village of Unadilla for the report of a domestic dispute. 

A preliminary investigation determined that during the call a member of the state police discharged their Division-issued firearm, striking the suspect. 

The individual was transported to an area hospital. 

The investigation is ongoing. 

Updates will be posted on the online newsroom as available. 


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