Rep. Rashida Tlaib (D-MI) was forced to apologize Saturday after encouraging the crowd at a Bernie Sanders rally in Iowa to boo the 2016 Democratic presidential nominee, Hillary Clinton.

Tlaib appeared alongside fellow progressive “squad” member, Rep. Ilhan Omar (D-MN) at a Sanders event in Clive, Iowa, on Friday, and instigated a chorus of loud “boos” when the former Secretary of State’s name was mentioned. The event’s moderator, Dionna Langford, tried to control the crowd, encouraging them to be “classy,” but it was too late — the exchange was widely reported and caught on camera.

BREAKING: At a @BernieSanders rally in Iowa tonight, a leading Sanders’ surrogate @RashidaTlaib led the crowd in booing @HillaryClinton. pic.twitter.com/AKdi2psI2h — Christopher J. Hale (@chrisjollyhale) February 1, 2020

Tlaib was likely responding to comments Clinton has made during the publicity tour for her Hulu documentary, “Hillary,” which premiered last weekend at the Sundance Film Festival. In the film, Clinton calls Sanders unlikable and fake.

Clinton doubled down on her comments in an interview with Variety last week, angering Sanders supporters who reminded Clinton that Sanders campaigned for her in 2016 despite believing he’d been unfairly shut out of the nomination process by a Democratic “establishment” that crowned Clinton the nominee before the campaign even began in earnest.

Clinton surrogates and Democratic strategists erupted in anger at Tlaib, urging Sanders to “speak out” against “his surrogates” and encourage unity among Democrats, and suggesting that Tlaib comments were “disappointing and beneath the dignity of the offices these women hold.”

Tlaib was eventually forced to issue an apology for her remarks.

“I am so incredibly in love with the movement that our campaign of #NotMeUs has created. This makes me protective over it and frustrated by attempts to dismiss the strength and diversity of our movement,” Tlaib said on Twitter.

“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,” she added. “I will continue to strive to come from a place of love and not react in the same way of those who are against what we are building in this country. This is about building a just and equitable future for my two boys, children across the country, and future generations.”

The Sanders campaign has reportedly been telling surrogates like Tlaib to exercise “restraint” on the campaign trail, concerned that Clinton is trying to “bait” aides and supporters into unprofessional outbursts.

Politico reports that “Sanders’ campaign told staffers internally to not discuss Clinton’s comments, and Sanders released a statement saying he is focusing on impeachment and that ‘together, we’ will defeat President Donald Trump. His aides are also urging his online fans to volunteer for him instead of tweeting about Clinton.”

“In [Clinton’s] remarks, published two weeks before the Iowa caucuses,” the outlet ads, “they see a political establishment that is trying to stop him as he rises in early-state polling.”

Sanders has enough trouble without his “squad” encouraging a Democratic civil war. Despite being neck-and-neck with former Vice President Joe Biden going into Monday’s Iowa caucuses, his campaign has suffered a spate of messaging disasters over the last several weeks, and the Sanders campaign is said to be fracturing internally.