The FBI is investigating fires at ballot boxes in the Pacific Northwest.

Investigators believe the fires in Vancouver, Washington, and Portland, Oregon, which destroyed hundreds of ballots, may be connected. In both incidents, authorities say explosive devices were used to set the fires. No arrests have been made.

People who used the ballot boxes over the weekend are encouraged to reach out to their local election officials to see if their ballot was one of the those that were destroyed. If it's determined their ballot was impacted, they can request a new one.

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In an attempt to prevent future attacks on ballot boxes, officials in Vancouver have hired more staff to monitor drop boxes.

Federal authorities warned that ballot drop boxes could be targeted by domestic violent extremists this election. Homeland Security released a bulletin in mid-September that stated it was concerned about the drop boxes being a target for destruction after tracking chatter on social media.

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