Mr. Ebisawa, 60, is being held in a federal jail in Brooklyn after being charged in 2022, along with three co-defendants, with international drug and weapons trafficking crimes. He has pleaded not guilty to those charges. He is scheduled to appear in Federal District Court in Manhattan on the new charges on Thursday. [...] In September 2020, he offered to sell 50 metric tons of uranium and thorium for $6.85 million. A week later, he told the undercover agent that he could supply plutonium that would be "better" than uranium for Iran's purposes. He added that he did not have a license to sell such materials. The transaction, the agent acknowledged, would be "very quiet and illegal." As part of the trafficking scheme, the indictment says, Mr. Ebisawa sent the undercover agent a list of weapons he wanted, including surface-to-air missiles and AK-47 assault rifles. He then sent the agent a picture of the leader of an ethnic insurgent group in Myanmar who is an unindicted co-conspirator in the scheme, referring to the person as "No. 1."