(CNN) The Justice Department is investigating the leak last year of confidential reports about Michael Cohen's personal bank records which led to revelations that the former Donald Trump lawyer was profiting by selling his access to the White House, two people familiar with the matter say.

Prosecutors with the US attorney's office in the Northern District of California are leading the criminal investigation, one of the people said, and criminal charges in the case could be announced soon.

The bank transactions of Cohen became public last May when lawyer Michael Avenatti posted a memo online outlining numerous payments to Cohen from a company linked to a Russian oligarch, pharmaceutical giant Novartis, AT&T, which owns CNN, and others.

The payments went through Essential Consultants LLC, a shell company Cohen created that he also used to make hush money payments to Avenatti's client, adult-film actress Stormy Daniels, to silence her allegations of an affair with Trump. Trump has denied the affair. At the time, Cohen's attorney alleged his bank records were illegally obtained.

CNN has reviewed documents that appear to show these payments. CNN has not independently authenticated the documents.

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