(CNN) Facebook and Twitter are reviewing and taking down posts that spread disinformation about how and when to vote on Election Day.

A senior official from the National Association of State Elections Directors told reporters Tuesday that the group flagged election disinformation to both social media companies.

Ahead of last year's midterm elections, Facebook and Twitter declared such posts against their policies and created methods for states to flag election-related misinformation for removal.

"I have (reported disinformation) today and over the last couple days. We've seen a couple things on Twitter. We've seen a couple of things on Facebook," the official said.

"I've seen one that was 'It's raining, so Election Day has moved to Wednesday,' " the official added said. "I saw one from a county in a state that voting machines in a precinct were not functioning and that the lines were super long, which we knew was misinformation because that particular county uses vote centers and therefore doesn't have precincts."

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