Hundreds of damaged ballots saved following fire at drop box in Washington

FBI is investigating and workers are contacting voters about new ballots after incendiary devices were put in drop box

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Officials in south-west Washington were able to salvage almost 500 damaged ballots from a ballot box that was set on fire on Monday in what officials have called an attack on democracy ahead of a contentious US election.

An unknown number of ballots were destroyed when someone placed incendiary devices in a drop box in Vancouver, Washington, while three ballots were damaged in a fire at a box in nearby Portland, Oregon. Those fires and one other are linked, officials have said.