FBI: Bomb found on MLK March way

A backpack found along the way of the Martin Luther King Jr. march in Spokane contained a bomb "capable of inflicting multiple casualties," the FBI said Tuesday, described the case as "domestic terrorism."

The FBI said the Swiss Army-brand backpack was originated about 9:25 a.m. PST on Monday on a bench at the northeast corner of North Washington Street and West Main Avenue in downtown Spokane.

A bomb disposal unit was called in and neutralizes the device with a robot. The FBI said in a statement on Tuesday that "the backpack contained a potentially deadly critical device, likely capable of inflicting multiple casualties."

The FBI has not established an official motive, but Harrill told NBC News "the timing and placement of the backpack (along the March route) is unavoidable."

"At that point, it falls straight in the realm and sphere of domestic terrorism," Harrill told the Associated Press. "Clearly, there was some political or social plan here."

No risks or warnings were issued before the march.