Congresswoman Rashida Tlaib says she regrets booing 2016 Democratic nominee Hillary Clinton at an event in Iowa.
It follows some criticism after footage of Friday’s event was posted on Twitter by an audience member.
Ms Tlaib, also a Democrat, led the booing in response to Ms Clinton saying in a documentary that “nobody likes” presidential hopeful Bernie Sanders.
Ms Tlaib later said that she had allowed her feelings about Ms Clinton’s remarks “to get the best of me”.
“I know what is at stake if we don’t unify over one candidate to beat [President Donald] Trump and I intend to do everything possible to ensure that Trump does not win in 2020,” she tweeted.
“In this instance, I allowed my disappointment with Secretary Clinton’s latest comments about Senator Sanders and his supporters get the best of me. You all, my sisters-in-service on stage, and our movement deserve better.”
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How did the booing come about?
The Michigan representative was taking part in a panel event with fellow Democratic congresswomen Pramila Jayapal and Ilhan Omar, held at a folk music concert in Iowa on Friday.