During an 11 a.m. ceremony attended by family and friends, Astorino was set to unveil a memorial plaque at the Kensico Dam Memorial Walkway in Valhalla.
Lemm, 45, was from West Harrison and worked as a detective for 15 years with the New York Police Department in the Bronx. He was serving his third overseas tour when a suicide bomber attacked his convoy in Afghanistan in December 2015.
Lemm enlisted in the 105th Airlift Wing based at Stewart Air Base in Orange County in 2008, serving as a security force member. He previously served in the military from 1988 to 1996. His prior deployment experience included missions to Afghanistan from January to June 2013 and to Iraq from June to December 2011.
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