Michigan Gov. Rick Snyder is expressing his condolences to the families of victims killed in the attack at the Washington Navy Yard.
In a statement Tuesday, the governor said the "senseless" violence is "unthinkable and leaves a mark of sadness on the hearts of all Michiganders."
One of the dozen people killed Monday was 59-year-old Michael Arnold, who grew up in the Detroit suburb of Rochester and returned to Michigan for Labor Day to visit his 80-year-old mother. Arnold worked at the Navy Yard on a team that designed vessels such as the USS Makin Island, an amphibious assault ship used by the Marine Corps.
Snyder notes President Barack Obama's call for American flags to be flown at half-staff. Flags should be returned to full-staff on Friday.