Bernie Sanders has linked Hillary Clinton to the widening Panama Papers scandal as the Democratic candidates wrangle to cast one another as unqualified to take the White House just two weeks out from the New York primary.

The Panama Papers scandal, which exposed massive-scale tax evasion by corporations and world leaders tied to a shady law firm in the country, feeds right into Sanders's campaign agenda. So far, the Panama Papers leaks have not included any politicians in the United States. But the leaks mesh seamlessly into Sanders' narrative against corporate corruption, fueled by populist anger toward a wealthy elite and establishment politics that he charges has facilitated it.

As more and more allegations of shady financial dealings came to light this week, Sanders tied Clinton to the scandal through her support for the 2009 Panama Free Trade Agreement. Opponents to the deal, including Sanders, said at the time would allow rich Americans to set-up offshore accounts and corporations to evade taxes. That's exactly what happened in the years since, and Sanders didn't skip a beat hitting Clinton over the head with it at a rally in Pennsylvania Wednesday.

"I don't think you are qualified [for president] if you supported the Panama Free Trade Agreement, something I very strongly opposed, which has made it easier for wealthy people and corporations all over the world to avoid paying taxes owed to their countries," Sanders told supporters at Temple University.

Both candidates appear to have thrown any semblance of courtesy out the door in recent days, as they gear up for what could be a contentious and close battle in the New York state primary on April 19. Both candidates are crisscrossing the state and turning up the heat on their opponent, working to take a large slice of New York's 247 delegates.

At the same rally at Temple University on Wednesday, Sanders said that Clinton seemed to be "getting a little bit nervous," after he racked up a 14-point victory in Wisconsin the night before.

"We have won seven out of eight of the recent primaries and caucuses," he said. "And she has been saying lately that she thinks I am quote-unquote not qualified to be president."

Clinton spokesman Brian Fallon immediately took to Twitter Wednesday night, calling Sanders's tactics a "new low." Those same words were used 5 hours earlier in the subject line of an email from Sanders campaign manager Jeff Weaver. Weaver called the Clinton's campaign tactics a "new low" after an anonymous source told CNN that Clinton's campaign had plans to "disqualify" Sanders and "defeat him," and then focus on "unify[ing] the party later."

"I don't know why he said 'quote-unquote,' — she's never said that," Clinton communications Deputy Communications Director Christina Reynolds added in a fundraising email Thursday. "This is a ridiculous and irresponsible attack for someone to make."

Hillary Clinton did not say Bernie Sanders was 'not qualified.' But he has now - absurdly - said it about her. This is a new low. — Brian Fallon (@brianefallon)April 7, 2016

During a Wednesday morning interview with MSNBC, Clinton questioned her rival's understand of the issues, but stopped short of saying he was "unqualified" to hold the country's top job. Clinton was commenting on criticism leveled at the senator about a New York Daily News interview published Tuesday, particularly over his lack of specificity on his plans to break up big banks.

"I think he hadn't done his homework and he'd been talking for more than a year about doing things that he obviously hadn't really studied or understood," Clinton said on MSNBC's Morning Joe. "That does raise a lot of questions."

On Thursday, Sanders reacted angrily to the escalation of attacks, saying he would focus on the important issues in his campaigns, had no plans to back down. He is currently lagging behind Clinton in polls by 10 points in New York — a state the senator has long emphasized is key to his campaign moving forward, mostly for the large number of delegates up for grabs on April 19. Clinton, who served as the state's senator for eight years, has already clinched 40 of the state's 44 superdelegates, who can change their support for a candidate at any time leading up to and even at the Democratic National Convention in July.

"If Secretary Clinton thinks that just because I'm from a small state in Vermont and we're gonna come here to New York and go to Pennsylvania and they're gonna beat us up and they're gonna go after us in some kind of really uncalled for way, that we're not gonna fight back, well we got another — you know, they can guess again because that's not the case," Sanders told reporters ahead of an address to the AFL-CIO's annual convention in Philadelphia on Thursday. "This campaign will fight back."

Less than a hundred miles away in New York, Clinton appeared ready to try to establish a slight détente by deflecting criticisms back toward the Republican candidates when asked about Sanders' allegation that she is unqualified to be president on Thursday.

"I don't know why he's saying that, but I will take Bernie Sanders over Donald Trump or Ted Cruz anytime," she remarked. "So, let's keep our eye on what's really at stake in this election. We have Republicans whose values are so antithetical to what's right for New York or right for America."

Hillary Clinton just responded to Bernie Sanders saying she's 'unqualified' to be president. Here's the video: — Jason Morrell (@CNNJason)April 7, 2016