 -- New hidden camera videos made public today by the government show a former American nuclear physicist covertly meeting with a man who he believed to be a Venezuelan intelligence officer in order to sell his expertise, as well as classified information, to the South American nation.

In one from 2008, nuclear physicist Pedro Mascheroni, former scientist in the X-Division of the Los Alamos National Laboratory in the 1980s, tells the other man, who is really an undercover FBI agent, that Venezuela could test a nuclear bomb in the Pacific to put the U.S. on notice.

“Everybody sees it. You don’t kill anybody. Now you tell the United States, ‘Not only do we have this, but we have [these] other designs… You have to come up and say to the other nations, 'We are going to be, we’re going to have an umbrella for everybody. If any nation outside Latin America attacks any nation inside Latin America, we are going to retaliate with a nuclear bomb,'" he says,

Mascheroni is a naturalized American citizen from Argentina.

In other audio recordings, referenced in court documents, Mascheroni speaks to his wife, another former worker at LANL, about his plans.

“This is very dangerous and I am doing it for money... I am, I told you, I’m not an American anymore. This is it,” Mascheroni says.

In 2013 Mascheroni pleaded guilty to several of the counts involving transmitting restricted information and making false statements to federal agents. He attempted to withdraw his guilty plea last summer, but the court denied the motion. Today the Justice Department announced Mascheroni has been sentenced to 60 months in prison, followed by three years of supervised release.

"[The] defendant’s aims were never noble, or part of some selfless journey that he had undertaken for the greater good of his fellow citizens,” the U.S. government wrote in a sentencing memorandum in January. “Rather, his actions were criminal to their core."

In response to the government’s stinging sentencing memorandum, Mascheroni’s defense argued that he was something of a mad scientist “entrapped” by the government.

“Anyone who has spent time with Dr. Mascheroni knows that he is completely and hopelessly obsessed with correcting the errors he perceives in the National Laboratories’ pursuit of nuclear fusion energy. This obsession has controlled his life since he lost his security clearance in 1988. Providing Dr. Mascheroni with a willing, receptive, well-funded, and non-critical audience for his scientific theories was the functional equivalent of providing crack to a cocaine addict,” the defense said in a motion last week.

“We simply cannot allow people to violate their pledge to protect the classified nuclear weapons data with which they are entrusted,” Assistant Attorney General for National Security John Carlin said in a DOJ release. “Today’s sentencing should leave no doubt that counterespionage investigations remain one of our most powerful tools to protect national security.”

Mascheroni’s wife also pleaded guilty in 2013 to conspiracy and false statements. She was sentenced last August to just over a year in prison and three years supervised release. Neither the Venezuelan government, nor any Venezuelan officials, were accused of any wrongdoing in the case.

[Editor's Note: This report has been revised to clarify that Mascheroni's statement about "doing it for the money" was made to his wife and not to the undercover federal agent, as the original version of this report implied.]