Trooper Mark A. Ondus became a Member of the New York State Police on April 11, 1994. He entered into a service retirement from the New York State Police after 26 years of service on January 20, 2021.
Trooper Ondus was approved for a World Trade Center Disability Retirement effective March 27, 2025. On October 9, 2025, he died as a result of colon cancer stemming from his assignment to the World Trade Center site, following the terrorist attacks on September 11, 2001.
In response to the events of 9/11, Trooper Ondus was assigned to aid with the search and recovery efforts in New York City, as part of the New York State Police Detail.
Trooper Ondus is survived by his wife, their three sons and daughter.