Hillary Clinton just unleashed one of her most stinging critiques yet on Donald Trump

Hillary Clinton's campaign launched an all-out assault against Donald Trump on Wednesday over Trump University, the controversial, for-profit school that has come under increased fire for its programs.

The assault came on several fronts from both Clinton and her campaign - via email, on Twitter, and at a rally in New Jersey.

Clinton's attacks came the day after hundreds of pages of internal documents were released in connection with an ongoing lawsuit against the now-defunct program on real estate and investing. The documents include sales and marketing "playbooks" from 2007 through 2010 that advised instructors on how to sell the courses to students.

"Trump and his employees took advantage of vulnerable Americans encouraging them to max out their credit cards, empty their retirement savings, destroy their financial futures, all while making promises they knew were false from the beginning," Clinton said at a Newark rally, according to CNN reporter Dan Merica.

"This is just more evidence that Donald Trump himself is a fraud. He is trying to scam America the way he scammed all those people at Trump U," she said.

Meanwhile, Clinton's press shop sent out several emails about Trump University on Wednesday, highlighting news stories about the document dump.

The articles - from Reuters, The New York Times, The Wall Street Journal, and The Washington Post - had unflattering headlines like, "Trump University told students how to 'cash in' on housing crash" and "Former Trump University Workers Call the School a 'Lie' and a 'Scheme' in Testimony."

The Clinton campaign has also been using Republican politicians' own words to make a point about how prominent members of the party  have criticized Trump over Trump University.

Clinton's campaign Twitter account on Wednesday retweeted a March tweet from 2012 Republican presidential candidate Mitt Romney that called Trump a "phony" and "fraud."

"Here's what I know," Romney tweeted on March 3, the day he gave a high-profile speech coming out against Trump's candidacy. "Donald Trump is a phony, a fraud. His promises are as worthless as a degree from Trump University."

Romney is still speaking out against Trump, but another prominent Republican - Florida Sen. Marco Rubio - has come around to supporting Trump since dropping out of the race for the Republican presidential nomination.

Clinton campaign press secretary Brian Fallon, also on Wednesday, resurfaced a February tweet from Rubio that he posted while he was still battling Trump for the nomination.

"Trump University duped everyday Americans - and Donald Trump made millions off of it," Rubio tweeted, with a link to his website.

Fallon also cited an old tweet from Texas Sen. Ted Cruz, another former Trump rival who hasn't said yet whether he'll support the real-estate mogul's White House bid:

The Trump campaign launched a counterattack of his own with a video of former Trump University students speaking out in support of the program.

Trump remains enmeshed in multiple lawsuits filed by former students of Trump University and faces a third fraud suit from New York Attorney General Eric Schneiderman, which likely won't go to trial until after the November election. The suits accuse Trump of defrauding thousands of students with worthless classes on real estate and investing.

Abby Jackson contributed to this report.