Harrill said the FBI isn't ready to assign any motive to whoever left the bomb. Nor do they have a suspect, he said, although the agency does have "a number of important, fruitful leads" from the public.
On Monday morning, about half an hour before the parade was to begin, three city workers found a backpack in a parking lot along the parade route, close to wear marchers would have assembled. They called the police, who sealed off several blocks, called in the FBI and rerouted the parade.
The backpack was packed with T-shirts and an incendiary device that "did appear to be viable" and could have caused multiple casualties, according to the FBI.
"This entire event and potential tragedy was averted by three alert citizens who confronted what they knew to be out of place, [leading to] an entire professional sequence of events," Harrill said.
Spokane Police were again today responding to reports of a suspicious package, this time a suitcase sitting on a sidewalk. A police spokeswoman said it does not appear to be another bomb, but they're taking every precaution.
"In this era, you can't ignore that," Harrill said. "It regrettably does require this kind of response because, occasionally, it will be something far more nefarious."