Special counsel Robert Mueller’s investigation into Trump’s connections with Russia is not over, as the news breaks that several weeks ago, Mueller issued a subpoena for Trump’s financial records with Deutsche Bank.

Special prosecutor Robert Mueller zeroed in on President Donald Trump’s business dealings with Deutsche Bank AG as his investigation into alleged Russian meddling in U.S. elections widens.

Mueller issued a subpoena to Germany’s largest lender several weeks ago, forcing the bank to submit documents on its relationship with Trump and his family, according to a person briefed on the matter, who asked not to be identified because the action has not been announced.

“Deutsche Bank always cooperates with investigating authorities in all countries,” the lender said in a statement to Bloomberg Tuesday, declining to provide additional information.

Deutsche Bank for months has rebuffed calls by Democratic lawmakers to provide more transparency over the roughly $300 million Trump owed to the bank for his real estate dealings prior to becoming president. Representative Maxine Waters of California and other Democrats have asked whether the bank’s loans to Trump, made years before he ran for president, were in any way connected to Russia. The bank previously rejected those demands, saying sharing client data would be illegal unless it received a formal request to do so. Trump has denied any wrongdoing.

The significant thing about this development is that Deutsche Bank is the only major bank in the world that still does business with the notoriously bankruptcy-prone Trump — and Deutsche Bank is also notorious for being caught several times laundering money for Russian interests.