George Nader, the United Arab Emirates lobbyist who set up a much-scrutinized meeting between a Trump administration emissary and an associate of Vladimir Putin’s in early 2017—and who reportedly appeared at the White House “frequently” early in Trump’s tenure to discuss Middle East policy—has been arrested and indicted on previously sealed charges of possessing child pornography, the Justice Department says. An affidavit filed by an FBI agent in April 2018, when Nader was initially charged, says 12 videos “that appear to be visual depictions of minors engaged in sexually explicit conduct” were discovered on an iPhone seized when he was stopped at Dulles airport in Virginia on Jan. 17, 2018 during an unnamed and “unrelated” investigation; previous reporting indicates that Nader was questioned on that day by investigators working for special counsel Robert Mueller. Nader subsequently became a cooperating witness in Mueller’s investigation. The DOJ says he was arrested Monday at John F. Kennedy Airport in New York City, whereupon the documents related to his case were unsealed.

Nader, an American citizen, was previously convicted of “transporting sexually explicit materials in foreign commerce” in Virginia in 1991 and of sexually abusing minors in the Czech Republic in 2003. Despite this history, he made connections within the Trump campaign and administration in 2016 and 2017 that allowed him to become involved in discussions of policy toward the UAE (with which the U.S. has allied in seeking to marginalize Iran) and Russia.

The New York Times has reported, for instance, that Nader met with Donald Trump Jr. at Trump Tower in New York City in August 2016 to convey that “the princes who led Saudi Arabia and the United Arab Emirates were eager to help his father win election as president” and pitch a social-media plan involving an Israeli company. (Though Saudi Arabia and the UAE are allies, there does not appear to be evidence that Nader ever worked formally for the Saudi government.) According to Mueller’s special counsel report, Nader later set up a January 2017 meeting in the Seychelles between informal Trump adviser Erik Prince (the founder of Blackwater, who is also Betsy DeVos’ brother) and Kirill Dmitriev, who runs a Russian sovereign wealth fund and meets on a regular basis with Vladimir Putin. (Per the report, Dmitriev and Nader became acquainted through his fund’s work with the UAE; the AP says Nader worked with Prince in Iraq.) The report also says that Nader was involved in discussions about a Russia-U.S. “reconciliation” proposal that Dmitriev created with a U.S. hedge fund director named Rick Gerson, who is a friend of Jared Kushner’s. (Nader’s name appears in the report 138 times.)

Finally, the AP and New York Times have reported that Nader worked with Republican fundraiser Elliott Broidy to pitch the Trump White House on plans for Saudi Arabian and UAE military cooperation with the United States. Axios has written that Nader “visited the White House frequently during the early months of the Trump administration” and was “friendly with former chief strategist Steve Bannon.” The AP says that Broidy helped arrange for Nader to be photographed with Trump in 2017; you can see the picture of Nader and Trump on the Times’ site.

Neither Nader nor any Trump figures have been charged with crimes related to the activities above, though Mueller’s report notes that the special counsel’s office was unable to fully investigate the Seychelles meeting because relevant text messages between Prince and Bannon had been deleted; House Intelligence Committee Chairman Adam Schiff has also referred Prince’s House testimony on the matter to the Department of Justice for potential perjury charges. Though it was reportedly a subject of Mueller’s investigation, Nader’s meeting with Trump Jr. is not addressed in the special counsel’s report.