An investigation is underway into ballot box arson in Portland, and across the river in Vancouver. Fires damaged a total of three ballot dropboxes, two of the incidents were early Monday. Portland Police say someone put an incendiary device on the outside of the box just outside the Multnomah County Elections office. The fire suppression system inside the box limited the damage to three ballots and those voters are being contacted. Authorities believe all of the cases are related.