UPDATE: O'Donnell says it was an error in judgment to run this story without verifying it with another source, and apologizes to Trump:

Lawrence O'Donnell announced this potential bombshell on Last Word last night. He added caveats -- "if true" -- but come on, at this point I'd be surprised if it wasn't true!

"We begin with the breaking news from Deutsche Bank that Deutsche Bank has Donald Trump's tax returns. That is not exactly what Deutsche Bank said in its redacted legal filing today, but it is what one source close to Deutsche Bank has revealed to me about the financial documents in the bank's possession," he said.

He then described how he came to that conclusion, then continued:

"The subpoenas in question are from the House Intelligence committee and House Financial Services committee. Those committees told the court they have subpoenaed Trump family financial records and tax returns from Deutsche Bank as part of an investigation of Russian money laundering and potential influence on the president. The information publicly disclosed today by Deutsche Bank is so far consistent with what a source close to Deutsche Bank has revealed to me about the Trump-related financial documents in Deutsche Bank's possession.

"The information the source has revealed to me is also consistent with New York Times reporting tonight saying, quote, 'Current and former bank officials have said Deutsche Bank has portions of Mr. Trump's personal and corporate tax returns from multiple years as part of the reams of financial data it has collected over its two-decade relationship with him. The information revealed to me goes a few very important steps beyond that.

"The source close to Deutsche Bank says that the Trump tax returns reveal that the president pays little to no income tax in some years and the source says that Deutsche Bank is in possession of loan documents that show Donald Trump has obtained loans with co-signers and that he would not have been able to obtain those loans without co-signers. The source close to Deutsche Bank says that the co-signers of Donald Trump's Deutsche Bank loans are Russian billionaires close to Vladimir Putin.

"If true, that would explain every kind word Donald Trump has ever said about Russia and Vladimir Putin. If true. If true, that would be a significant factor in Vladimir Putin's publicly stated preference for presidential candidate Donald Trump over presidential candidate Hillary Clinton."

Can't wait to see tomorrow's tweets. Oh boy, is this gonna be great!

Update: Remember this?