Philadelphia (CNN) The simmering strife between House Democratic leadership and the caucus's "squad" of progressive insurgents boiled over this weekend amid a barrage of attacks, in the press and on social media, against the diverse band of congressional newcomers.

Then President Donald Trump intervened.

With a few racist tweets , Trump accidentally unified -- at least for a day -- congressional Democrats after their most pointed internal battle since the new House majority took office at the beginning of the year.

Trump, in a series of Sunday morning posts, targeted the outspoken progressive congresswomen, demanding they "go back and help fix the totally broken and crime infested places from which they came."

"These places need your help badly, you can't leave fast enough," the President tweeted. "I'm sure that (House Speaker) Nancy Pelosi would be very happy to quickly work out free travel arrangements!"

Pelosi -- who has spent much of the last week swept up in a growing rift with Reps. Alexandria Ocasio-Cortez of New York, Rashida Tlaib of Michigan, Ilhan Omar of Minnesota and Ayanna Pressley of Massachusetts -- fired back less than two hours later, defending her members and calling Trump's comments "xenophobic."

"When @realDonaldTrump tells four American Congresswomen to go back to their countries, he reaffirms his plan to 'Make America Great Again' has always been about making America white again," Pelosi tweeted. "Our diversity is our strength and our unity is our power."

Pelosi herself made comments that appeared to anger the congresswomen — known on Capitol Hill as "the squad" — and led one of the them, Ocasio-Cortez, to suggest the Democratic leader was "singling out freshman congresswomen of color." The conflict has muddled the party's response to the migrant detention crisis at the US-Mexico border and fueled new anger among progressive activists.

Tension reaches a boiling point

Tension within the Democratic Party came to a head Friday night, following a day of reported potshots from congressional aides. The House caucus's official Twitter account attacked a top aide to Ocasio-Cortez over a June tweet criticizing another member's vote for a controversial border funding bill, telling her chief of staff Saikat Chakrabarti to keep Rep. Sharice Davids' "name out of your mouth."

The post set off alarm bells in Philadelphia, where thousands of liberal activists and a handful of progressive lawmakers gathered for the annual Netroots Nation summit . Angst over party leadership's handling of the situation on the border mixed with outrage over the aggressive -- and unexpected -- tweet, which initially left many wondering if it was sent by a rogue staffer.

This tussle surfaced tensions that go well beyond the halls of Capitol Hill and escalated growing discord inside the Democratic Party amid a contentious presidential primary.

Frustrations among establishment figures were reignited by the sharp, and many said offensive, criticism lodged by Chakrabarti after the border bill vote and the continued threat of primary challenges to sitting Democratic members. Justice Democrats, the group that backed Ocasio-Cortez's successful 2018 primary campaign, threatened to repeat the feat next year and in the process has drawn more visceral scorn from the offices of moderate lawmakers.

Future of the Democratic Party

Immigration and Customs Enforcement began carrying out raids on undocumented immigrants Sunday in major US cities.

"With ICE raids occurring this weekend, deaths of children at the border camps, and a continued blank check for the administration's racist deportation machine, we will be focusing on the real crisis at hand and we urge Democratic leadership to do so as well," more than a dozen progressive groups, including Justice Democrats, Indivisible and She The People said in a joint statement Saturday evening.

While the presidential candidates, led by Massachusetts Sen. Elizabeth Warren, turned the screws on the Trump administration's handling of the border crisis during their forum, chatter in and outside the Pennsylvania Convention Center turned on what they viewed as a squandered opportunity to highlight deprivation at detention centers and fury over leadership's apparent decision to dial up its fight with the progressive newcomers.

"If four votes are so inconsequential, why even bring them up?," Daily Kos founder Markos Moulitsas, who co-moderated the presidential forum, said Saturday of Pelosi's comments to the New York Times' Maureen Dowd last week. "We have a serious problem with turnout among young voters and voters of color. So why would you take people who are probably the best tools for getting those voters out to the polls next year, why would you start a feud with them? It makes no sense."

Pelosi in her interview with Dowd bristled at the backlash over the border bill and, in downplaying their influence, infuriated a progressive base that views Reps. Ocasio-Cortez, Ayanna Pressley, Rashida Tlaib and Ilhan Omar -- the only dissenting votes in the caucus -- as the party's future.

"All these people have their public whatever and their Twitter world," Pelosi told the Times. "But they didn't have any following. They're four people and that's how many votes they got."

Ocasio-Cortez responded on Twitter by listing a series of unflattering remarks the speaker has made about her and the progressive left agenda. But Pelosi made no apologies for her comments this week on Capitol Hill even as she asked for unity during a closed-door meeting with her caucus.

Asked on Thursday about Ocasio-Cortez and Pelosi's exchanges, Warren during a trip to Wisconsin ahead of her Netroots appearance said the squabbling would ultimately strengthen the party.

"I think it's great that we have a lot of new voices in the Democratic Party. They bring new energy, and they bring an excitement to people who feel like they've been sidelined forever," Warren told reporters. "So I'm just glad to see a lot of folks in it. I know it gets bumpy. But I'm glad to see people fighting."

At a panel in Philadelphia on Friday afternoon, Democratic Rep. Pramila Jayapal, co-chair of the Congressional Progressive Caucus, pushed back cautiously against the speaker's remarks to the Times.

"I don't think those comments were helpful to a broader picture of how we build progressive power in the House and what it looks like relative to overall Democratic power," Jayapal said.

But feelings among activists at Netroots were more raw, and their words less diplomatic, especially after the party caucus's official account delivered its Friday night broadside.

"I need to find new language because counterproductive doesn't adequately express how foolish and how un-strategic and wrongheaded this has been," Working Families Party national director Maurice Mitchell said, adding that House Democrats are "wasting gunpowder on their own members instead of focusing like a laser on the white Christian identity movement that Trump rode into the White House."

Yvette Simpson, chief executive of Democracy for America and a former Cincinnati city councilwoman, also told CNN the House Democrats should focus on Trump and back off the new generation of lawmakers.

"The idea that at the most critical moment for our party and for country, party leadership is attacking the most energetic and the most bold of us and, frankly, our present and our future, is appalling to me," Simpson said.

Focus on border crisis

Earlier in the day, three of the four "squad" members shared a stage for a keynote panel titled, "Making Herstory: The Women who are Shifting the Balance of Power in Washington." They avoided any direct mention of the storm around them and Pressley seemed to dismiss it all as a distraction from their work.

"It's our job to create space for those voices to be heard," she said. "And that's what guides me in this work every day -- not palace intrigue."

Warren's public debut on the presidential forum stage livened up the convention-goers, who gave her a standing ovation before she could say a word. A longtime favorite of the Netroots crowd, dating back to before her first Senate run, Warren delivered the forceful message on the border crisis many hoped would dominate conversation throughout the weekend.

"To anyone out there who's working in the system, understand -- you abuse immigrants, physically abuse immigrants, you sexually abuse immigrants, you fail to get the medical care that they need, you break the law of the United States of America," she said, before referring to her pledge, which she made as part of her immigration proposal this week, to pursue those allegations if she's elected.

"Donald Trump may be willing to look the other way, but President Elizabeth Warren will not," she said. "On my first day, I will empower a commission in the Department of Justice to investigate crimes committed by the United States against immigrants."