Jess Mazour was announced as Sanders' Iowa political director in March and was let go from the team in recent weeks. She previously worked as an organizer for the progressive group Iowa Citizens for Community Improvement.
A Sanders aide on Wednesday confirmed Mazour's departure on condition of anonymity. The aide wasn't authorized to discuss personnel matters.
The news of her departure was first reported by The Washington Post.
While the team still has a number of original top-level staffers in place in Iowa, the news of Mazour's departure comes as Sanders has also drawn headlines for staff troubles in New Hampshire, where his state director has been replaced.
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