With the exception of Donald Trump, no one name has surfaced as frequently—or drawn as much scrutiny—in the present Russian melodrama as Paul Manafort. Facing active investigations by the F.B.I., the Treasury Department, and Select Intelligence Committees in both the House and Senate, Trump’s former campaign chairman has emerged as a key figure in the unfolding Kremlingate scandal—even if the White House now claims that he had only a “limited role” on the Trump campaign. Last week, the Associated Press reported that Manafort was paid tens of millions of dollars by a Russian oligarch to advance Vladimir Putin’s agenda across Europe and the United States. Now, new media reports allege that Manafort also has a history of shady real-estate dealings and ties to more than a dozen bank accounts in Cyprus, raising questions about whether the longtime Trump ally was involved in money laundering.

According to a report by WNYC, Manafort has engaged in a series of curious real-estate deals over the past 11 years, all of which follow a pattern that law-enforcement experts say raises red flags. Between 2006 and 2013, the former Trump campaign chairman purchased three multimillion-dollar New York City–area properties in Trump Tower, SoHo, and Carroll Gardens, Brooklyn. Each home was purchased entirely in cash through various limited liability companies, and later transferred to Manafort. Then, between April 2015 and January 2017, Manafort borrowed approximately $12 million against the properties, according to public records obtained by WNYC. The details of Manafort’s dealings were previously uncovered by 377union.com.

There is no indication that Manafort’s New York City real-estate purchases suggest illegal behavior, nor have the transactions been investigated by authorities. But nine current and former law enforcement and real-experts told WNYC that the deals “merit scrutiny”:

Some said the purchases follow a pattern used by money launderers: buying properties with all cash through shell companies, then using the properties to obtain “clean” money through bank loans. In addition, given that Manafort is already under investigation for his foreign financial and political ties, his New York property transactions should also be reviewed, multiple experts said. One federal agent not connected with the probes, but with experience in complex financial investigations, said after reviewing the real estate documents that this pattern of purchases was “worth looking into.” The agent did not want to speak for attribution.

Manafort himself says he has nothing to hide. “My investments in real estate are personal and all reflect arm's-length transactions,” he wrote in a statement to WNYC. Following the report’s publication. “My personal investments in real estate are all ordinary business transactions. It is common practice in New York City and elsewhere to use an LLC to purchase real estate. These transactions were executed in a transparent fashion and my identity was disclosed.”

Still, the timing and nature of Manafort’s real-estate deals are questionable. According to a New York Times report published in August of last year, Manafort was reportedly designated to receive $12.7 million in undisclosed payments from a pro-Russian party in Ukraine between 2007 and 2012, coinciding with the 11-year period WNYC investigated. (Manafort has flatly denied any wrongdoing, saying in a statement at the time, “I never received a single ‘off-the-books cash payment’ as falsely ‘reported’ by The New York Times, nor have I ever done work for the governments of Ukraine or Russia.”)