Lawmakers led by Sen. Elizabeth Warren asked a key regulator to block Toronto-Dominion Bank‘s $13.4 billion acquisition of a regional U.S. bank because of allegations of customer abuse.

In a letter sent Tuesday to the Office of the Comptroller of the Currency obtained exclusively by CNBC, Warren cited a May 4 report from Capitol Forum, a Washington-based investigative news outfit, that alleged that TD used tactics similar to those in the Wells Fargo fake accounts scandal.

TD, a Toronto-based bank with 1,100 branches in the U.S., is seeking regulatory approval for the acquisition of Tennessee-based First Horizon. The massive deal, announced in February, is part of TD CEO Bharat Masrani’s push to expand in the American Southeast. Banks have been swept up in a wave of consolidation in recent years as lenders seek to gain scale, cut costs and invest in fintech to compete with megabanks like JPMorgan Chase and Bank of America.

“As TD Bank seeks approval from your agency to increase their market share and become the sixth-largest bank in the U.S., the OCC should closely examine any ongoing wrongdoing and block any merger until TD Bank is held responsible for its abusive practices,” Warren said.

TD employed a point system and bonuses to incentivize workers to open customer accounts and opt into overdraft protection, and workers could lose their jobs if they didn’t meet goals, Warren said in letter to acting OCC Comptroller Michael Hsu.

Workers were instructed to create four new accounts for each customer — checking, savings, online and a debit card — and opened accounts even if a consumer declined one of the options, according to the Capitol Forum.

That was one of several strategies cited by the news organization, including fabricating reasons to call consumers like fraud alerts in the hope of convincing them to open more accounts, opening new accounts rather than simply replacing missing debit cards, and misstating key aspects of overdraft programs to encourage their adoption. Problems existed in branches all along TD’s U.S. footprint, from Florida to Maine, the report stated.

CNBC couldn’t independently confirm the details of the Capitol Forum report, which cited current and former TD Bank employees as well as other sources.

In a four-paragraph response provided to CNBC by a bank spokesman, TD said the allegations in the Capitol Forum piece were “unfounded.”

“Our business is built on a foundation of ethics, integrity and trust,” the bank said. “At TD Bank, we put our customers first and are proud of our culture of delivering legendary experiences to customers. As part of routine and ongoing monitoring, TD Bank has not identified systemic sales practice issues at any time.”

The bank said it carefully manages compensation practices and “vehemently” objects to accusations of “systemic sales practice issues, or any other claims alleged in the article.”

“Finally, we strongly disagree with the article’s characterization of information presented as facts regarding TD Bank’s fraud procedures,” the bank said. “At TD Bank, protecting the security of our customers’ accounts and personal information is a top priority.”

The Capitol Forum report also alleged that the OCC, under previous leadership, had actually uncovered TD’s misconduct in 2017 as part of an industry sweep after the Wells Fargo scandal came to light the year before.

The report alleged that former acting Comptroller Keith Noreika — a Trump administration appointee whose law firm later represented TD in multibillion dollar transactions — opted to privately reprimand TD, rather than fining the company or publicly releasing its findings.

Noreika declined to comment to the Capitol Forum, but his employer, the white-shoe law firm Simpson Thacher & Bartlett, told the news outfit that Noreika was recused from all matters related to TD while heading the regulator.

“The OCC’s decision under Mr. Noreika to allow TD Bank’s rampant fraud and abuse to go unpunished, even after the agency’s troubling findings in its own investigation of the bank, has the potential to undermine the OCC’s authority and put consumer finances at risk,” Warren said. She added that the Biden administration has stated it would scrutinize bank mergers more closely.

The OCC didn’t immediately respond to a request for comment.

Apart from requesting that the First Horizon acquisition be blocked, the lawmakers asked the OCC to release the findings of its 2017 investigation into TD and reconsider whether penalties should be levied on the company. The letter was signed by Warren and U.S. Representatives Katie Porter, Al Green and Jesus Garcia.

TD said in February that it expected the First Horizon acquisition to close by the first fiscal quarter of 2023, subject to approval from U.S. and Canadian regulators. The deal will be scrapped if it doesn’t close by Feb. 27, 2023, according to the bank.