The union is hoping to parlay its strike against the "Big Three" into a historic organizing success in the U.S. South.
The shooting involved "multiple parties exchanging gunfire," police told a local news station.
Chattanooga's David Jean-Baptiste heaved in the victorious shot that he called "surreal."
A coalition of activists sent letters to hundreds of school districts warning them against a particular school bus operator.
5 children were killed: a kindergartner, a first-grader and three fourth-grade students.
Jackson, Chattanooga and Tulsa are among those chosen for a new initiative.
The shooting "puts a tremendous amount of pressure on the community."