Deutsche Bank has begun the process of providing financial records to New York state’s attorney general in response to a subpoena for documents related to loans made to Donald Trump, while his failed attempt to purchase the Buffalo Bills keeps coming back to haunt him.

Last month, the office of New York Attorney General Letitia James issued subpoenas for records tied to funding for several Trump Organization projects.

The state’s top legal officer opened a civil probe after Trump’s former lawyer Michael Cohen testified to Congress in a public hearing that Trump had inflated his assets.

Cohen at that time presented copies of financial statements he said had been provided to Deutsche Bank.

The bank is in the process of turning over documents, including emails and loan documents, related to Trump International Hotel in Washington, DC; the Trump National Doral Miami; the Trump International Hotel and Tower in Chicago; and the unsuccessful effort to buy the NFL’s Buffalo Bills.

The bank is already the subject of a joint investigation between the House Financial Services and Intelligence committees into Trump’s businesses and money laundering.

Deutsche Bank has been one of the few big banks willing to lend to the Trump Organization in recent years.

[New York Attorney General Subpoenas Deutsche Bank Top Trump Lender]

Trump’s businesses have borrowed more than $300 million from Deutsche to finance the company’s Florida golf course and hotels in Chicago and Washington, according to financial disclosures and public filings from 2012 to 2015.

Trump’s failed attempt to buy the Buffalo Bills now stands at the center of three separate Democratic investigations aimed at getting to the bottom of the president’s finances.

And if what happened earlier this week is any preview of what’s to come, those investigations seem likely to prompt legal battles long before they produce any new revelations.

Trump and his companies on Monday filed a lawsuit against one of the congressional committees probing his finances, as well as against the accounting firm he’s used for years.

Trump hopes a court will prevent that accounting firm from being forced to turn over detailed statements about Trump’s finances, including those he filed in connection with his proposed purchase of the Bills.

Cohen gave the House Oversight and Reform Committee back in February abbreviated financial statements showing that Trump inflated his net worth by $4 billion while trying to finance his bid to purchase the Bills in 2014, which failed when the NFL chose Terry and Kim Pegula as the team’s new owners.

Documents show Trump with a net worth of $4.56 billion as of June 30, 2012.

But in a March 31, 2013, statement, Trump reported his net worth as $8.66 billion, largely thanks to the addition of a new $4 billion line item labeled “brand value.”

Cohen testified that Trump inflated his net worth while seeking financing to buy the Bills – which, Democrats speculate, could be seen as bank fraud.