The alleged boss of the Japanese Yakuza has pleaded guilty to conspiring to traffic uranium and weapons-grade plutonium to an informant posing as an Iranian general.
Takeshi Ebisawa, 60, entered guilty pleas to a Manhattan court for six charges, according to the US Justice Department.
They included conspiracy to international trafficking of nuclear materials, international trafficking of nuclear material, narcotics importation conspiracy, conspiracy to possess firearms and money laundering.
He will be sentenced by a US federal district judge at a later date.
Some of the charges he has pleaded guilty to carry a minimum of 10 years in prison and a maximum of life behind bars.
Fake Iranian general told plutonium 'better' than uranium
In a statement, Southern District of New York Acting US Attorney Edward Kim said Ebisawa "brazenly trafficked nuclear material, including weapons-grade plutonium, out of Burma".
"At the same time, he worked to send massive quantities of heroin and methamphetamine to the United States in exchange for heavy-duty weaponry such as surface-to-air missiles to be used on battlefields in Burma and laundered what he believed to be drug money from New York to Tokyo," he said.
In early 2020, Ebisawa also informed an undercover agent he had access to large quantities of nuclear materials, and sent them photos and documents indicating he had possession of uranium.
The US Justice Department said an associate of its undercover agent then posed as an Iranian general.
Ebisawa offered to supply the fake Iranian general plutonium, which he described as "better" and "more powerful" than uranium.
The Justice Department later said it seized, with the assistance of Thai authorities, nuclear samples that were later proven in a laboratory to be detectable quantities of uranium, thorium and plutonium.
Both uranium and plutonium can be used in nuclear weapons.
Mr Kim said a multinational effort was required to ensure the alleged Yakuza boss was stopped.
"It is thanks to the extraordinary efforts of the [Drug Enforcement Administration's] Special Operations Division, the career national security prosecutors of this Office, and the cooperation of our law enforcement partners in Indonesia, Japan, and Thailand, that Ebisawa's plot was detected and stopped," he said.
ABC/Reuters