The Maryland couple accused of attempting to pass secret Navy secrets to a foreign government were indicted by a Grand Jury Tuesday on national security charges.

Jonathan and Diana Toebbe are both charged with one count of "Conspiracy to Communicate Restricted Data" and two counts of "Communication of Restricted Data," according to a Department of Justice press release Tuesday.

According to the release, 42-year-old Jonathan Toebbe sold "Restricted Data" concerning the design of nuclear-powered waships for almost a year with the help of his 45-year-old wife, Diana Toebbe. The couple sold the data to someone they thought was a representative of a foreign government, but who was an undercover FBI agent.

The attack submarine USS Virginia departs Naval Submarine Base New London en route to Portsmouth Naval Shipyard in Kittery, Maine in 2010 - file photo. (U.S. Navy photo/Petty Officer 1st Class Steven Myers)

NEIGHBOR SAYS COUPLE ACCUSED OF SELLING US SECRETS 'DIDN'T TALK TO ANYBODY,' CALLS ARREST 'BIG SHOCK'

Jonathan Toebbe worked for the Department of the Navy as a nuclear engineer and held an active national security clearance, giving him access to the restricted data.

The indictment comes after Toebbe was arrested last week in West Virginia after placing a removable memory card at a prearranged "dead drop," the Justice Department said.

The FBI said the couple's scheme began in April 2020, when Toebbe sent a package with Navy documents to a foreign government and signaled his interest in selling the country sensitive information. He also provided instructions on how to arrange the secret exchange in a letter to the foreign government.

Two people, man and woman, working together in office, FBI team.

Two people, man and woman, working together in office, FBI team. (This content is subject to copyright.)

"I apologize for this poor translation into your language. Please forward this letter to your military intelligence agency. I believe this information will be of great value to your nation. This is not a hoax," Toebbe said in the letter.

The indictment alleges that in June of this year, an undercover agent sent Toebbe a $10,000 cryptocurrency payment as a "good faith" gesture before he traveled to the West Virginia "dead drop" location. Once there, Toebbe placed a concealed SD card at the location while his wife acted as a lookout.

After retrieving the SD card, the undercover agent sent Toebbe a $20,000 cryptocurrency payment in return for the decryption key for the SD Card, which contained Restricted Data concerning nuclear reactors. 

Toebbe would go on to make a second "dead drop" of an SD card in Virginia in exchange for $70,000 in cryptocurrency, with that SD card also containing more Restricted Data about nuclear submarine reactors.

The world's first nuclear-powered submarine, the USS Nautilus was landmark in naval engineering when launched in 1954. She was later decommissioned in 1980 and now remains open to the public in Groton, Conn.

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According to a Fox News report last week, a review of what appeared to be the Toebbes' social media accounts revealed Diana Toebbe had several Facebook and Twitter posts voicing support for the Black Lives Matter movement, along with anti-Trump posts.

She is a teacher at the private Key School in Annapolis, MD, which indefinitely suspended her after her arrest.