Gunfire erupted inside the building at 9:38 a.m., according to Fuller, who said the facility was open at the time and that there may have been patients inside the building.
No one else was injured, and Fuller said the gunman opened fire with a handgun. It was not clear how many rounds were fired.
The victim's identities were not immediately released.
This is a breaking story. We will publish more information as it becomes available.