In his Republican nominee acceptance speech, Trump offered no serious policy other than a "stupid wall that will never get built," Warren said to applause at the Democratic National Convention.

The lawmaker from Massachusetts, who endorsed presumptive Democratic presidential nominee Clinton last month, has served as an attack dog for the Democrats against Trump. She has traded public jabs with the Republican nominee and on Monday painted him as divisive, dangerous and lacking concrete policy.

PHILADELPHIA — Sen. Elizabeth Warren tried to sow Democratic unity here Monday, turning barbs on Donald Trump and backing the policies of Hillary Clinton following two days of tension within the party.

Senator Elizabeth Warren speaks during Day 1 of the Democratic National Convention at the Wells Fargo Center in Philadelphia, Pennsylvania, July 25, 2016.

"Trump thinks he can win votes by fanning the flames of fear and hatred. By turning neighbor against neighbor. By persuading you that the real problem in America is your fellow Americans — people who don't look like you, or don't talk like you, or don't worship like you," Warren said at the Wells Fargo Center.

"That's Donald Trump's America. An America of fear and hate. An America where we all break apart. Whites against blacks and Latinos. Christians against Muslims and Jews. Straight against gay. Everyone against immigrants. Race, religion, heritage, gender — the more factions the better."

A favorite of progressive Democrats and fervent critic of Wall Street excesses, Warren attracts supporters similar to those drawn to Sen.Bernie Sanders. Speculation swirled around Warren as a possible vice presidential pick to assuage Sanders primary voters. Clinton eventually chose a more moderate pick, Sen. Tim Kaine of Virginia.

Warren endorsed Clinton on Monday, repeating the campaign slogan "I'm with her." She specifically highlighted Clinton's ideas on income inequality, climate change and wage equality, among other issues.

Warren's remarks followed some resistance to Clinton's expected nomination from both pro-Sanders delegates and thousands of protesters here. Some in the crowd shouted and chanted during Warren's speech even as she turned the heat on the bombastic Trump.

Warren contended that Trump only looks out for his own interests and will not fix a "rigged system." She said he "must never be president of the United States," to standing applause in pockets of the arena.

Warren criticized Trump for wanting to roll back regulations on the financial industry and cut taxes across the board. Warren argued that he has "no plans to make anything great for anyone except rich guys like Donald Trump."

"Trump's entire campaign is just one more late night Trump infomercial," Warren said to laughter.

Trump responded to Warren's speech on Twitter, saying she "just misrepresented me."

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