INDIANA / WISCONSIN — It is with profound sadness that colleagues, family members, and fire service communities across Wisconsin and beyond are mourning the loss of Tom Diener, who passed away on December 11, 2025, following a tragic highway incident while traveling for work related to public safety and emergency warning systems.

According to colleagues, Tom was traveling in Indiana alongside Carter Haen and Robbie Betts when the incident occurred. Tom succumbed to his injuries, while Carter and Robbie survived and are now facing a long road of recovery. The loss of Tom has sent shockwaves through the public safety community, where he was widely respected for his dedication, professionalism, and unwavering commitment to protecting others.

Tom Diener devoted his life to service. He proudly served as a Firefighter/Paramedic with the City of Oshkosh Fire Department and as a Lieutenant with the Town of Sheboygan Fire Department. Beyond his roles in fire and emergency medical services, Tom was also a business owner whose work focused on emergency warning systems—an extension of his lifelong mission to keep communities informed, prepared, and safe.

Those who worked alongside Tom describe him as a man of integrity, quiet leadership, and deep compassion. Whether responding to emergencies, mentoring fellow firefighters, or advancing public safety initiatives, Tom approached every responsibility with purpose and heart. His service left a lasting imprint not only on the departments he served, but on the countless lives protected through his work.

The loss is being felt profoundly by Tom’s family, friends, coworkers, and the broader fire service community. Colleagues have expressed deep concern and support for Carter Haen and Robbie Betts, holding them close in thought as they navigate the days ahead. The community has also asked for privacy and grace for all affected families during this difficult time.

In a statement, colleagues emphasized that Tom’s legacy will continue through action.

“In the days to come, we will honor Tom’s legacy by continuing our unwavering commitment to public safety and the work he believed in,” the statement read. “His mission, values, and dedication will not be forgotten.”

To honor Tom Diener’s life and service, a donation page has been established through the Professional Fire Fighters of Wisconsin Charitable Foundation, with proceeds benefiting Tom’s memory and supporting Carter Haen and Robbie Betts during recovery.

As communities reflect on this heartbreaking loss, Tom Diener is remembered not only as a firefighter and leader, but as a man who lived selflessly in service to others. His legacy will endure in the work he championed, the lives he touched, and the example he set for those who follow in his footsteps.