State Police announce that Major Mark A. Nielson will serve as the 38th Troop Commander of Troop K

Major Nielson, a 22-year veteran of the New York State Police, also worked for the Ulster County Sheriff’s Office as a Deputy Sheriff and the Town of Ulster Police Department as a Police Officer before joining the State Police in January of 2002.

Major Nielson’s first patrol assignment was Troop F, Zone 3, Ulster County.

In October 2007, he was promoted to Sergeant and assigned to Troop K (SP Cortlandt), until his transfer to Troop F in 2012.  In 2013, he was appointed to Station Commander and assigned to SP Ellenville.

Major Nielson was promoted to Lieutenant in February 2015 and assigned to various positions, including Assistant Zone Commander at Troop F (SP Monroe) and SP Kingston, Zone 1 Commander of the Special Investigation Unit.

In September 2019, Major Nielson was appointed to the rank of Captain and assigned to the Professional Standards Bureau – Southern Region. In 2020, he was transferred to Troop F, where he served as the Administrative Captain and later the Zone 3 Commander at SP Kingston.

In October 2023, he was appointed Major and assigned to Division Headquarters – Administration.

Major Nielson grew up in New Paltz, NY, and graduated from the State University of New York at Ulster in 1994.  He is married and has two grown children.   

Major Nielson’s assignment as the Troop K Commander was effective January 2, 2025. He replaces Major Kathryne M. Rohde, who was appointed to Staff Inspector - Professional Standards Bureau in Albany Headquarters.

Major Nielson’s command covers four counties in the Hudson Valley, including Columbia, Dutchess, Putnam, and Westchester. Operating from 17 facilities, the men and women of Troop K provide service to 62 towns, 39 villages, and nine cities.