ThinBlueNews remembers Border Patrol Agent Sean M. McDonough of the U.S. Department of Homeland Security, Customs and Border Protection, U.S. Border Patrol, whose End of Watch was Friday, May 1, 2026.
According to the Officer Down Memorial Page, Agent McDonough suffered a medical emergency while performing marine unit water training in Alexandria Bay, New York. ODMP lists his line-of-duty death as a duty-related illness and records his service with the U.S. Border Patrol as more than 19 years.
WWNY/7News reported that Customs and Border Protection Commissioner Rodney Scott announced Agent McDonough’s death after the Wellesley Island Border Patrol Station agent died while training along the St. Lawrence River. The local report said federal officials confirmed he went into cardiac arrest during the training.
Police1, citing Customs and Border Protection and a Watertown Daily Times report, also reported that Agent McDonough was participating in water training with the marine unit when he experienced chest pain, received CPR, and was taken to a hospital.
ODMP lists Agent McDonough as a U.S. Army and National Guard veteran. It says he is survived by his wife, two daughters, parents, two sisters, grandmother, two nieces, and a nephew.
This remembrance is offered with respect for Agent McDonough’s family, his Border Patrol colleagues, and the federal law-enforcement community carrying his memory forward.
Agent McDonough’s End of Watch is a solemn reminder that training, readiness, and public service can carry real sacrifice, and that those who answer the call deserve to be remembered with dignity.
Support the organization preserving official memorial records
ThinBlueNews creates original remembrance pages to honor law-enforcement sacrifice. ODMP is the nonprofit maintaining the national officer memorial record and providing support resources connected to fallen officers and their families.
Sources and attribution
- ODMP memorial page: Border Patrol Agent Sean M. McDonough
- WWNY/7News: U.S. Border Patrol Agent dies while training near Alexandria Bay
- Police1: Border Patrol agent dies following medical emergency during marine training
- ODMP donation page
Featured memorial image: ODMP profile portrait of Border Patrol Agent Sean M. McDonough with ThinBlueNews memorial overlay and source attribution. ThinBlueNews does not claim ownership of the source portrait.
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