Hundreds of ballots damaged after fire in Vancouver drop box and incendiary device set off in box in Portland

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Hundreds of early ballots cast for the US presidential election have been burned in two suspected attacks in Washington and Oregon, exacerbating tensions ahead of next Tuesday’s knife-edge contest.

Firefighters went to the scene after smoke was reported coming from a ballot drop box in the city of Vancouver in Washington state at 6.30am on Monday, according to local media.