More: CNN ANCHOR BRIANNA KEILAR: Happening now in the House investigation into Jeffrey Epstein, testimony from Epstein's longtime accountant Richard Kahn. He's being deposed behind closed doors today.

The House Oversight Chairman calls Kahn a, quote, "big witness.".

Lawmakers were expected to ask him, among other things, how Epstein accumulated his vast wealth and how he spent it.

Moments ago, a member of the House committee said Kahn provided some new information about the system that enabled Epstein to commit his crimes. The congressman also saying this:

REPRESENTATIVE SUHAS SUBRAMANYAM (D-VA): We can't get into the details of everything that was said, but one of the things that we did learn was that there was another head of state that was mentioned as having financial transactions with Jeffrey Epstein. Not an American one.

And then another person who was an accuser of Donald Trump was given a settlement by Jeffrey Epstein's estate. We did confirm that.