Russia’s Security Services (FSB) said on Tuesday it had arrested a Russian citizen suspected of transferring classified documents to Ukraine, opening an investigation into high treason amid a Russian offensive against its neighbor. “The FSB discovered that a Russian citizen (engaged in an act) of high treason by sending information to Ukraine to harm the security of the Russian Federation,” the security services said in a statement.

According to the press release, the unidentified resident, who ran an aircraft factory in the Moscow region, “photographed with a mobile phone pieces of plans for fighter aircraft parts, before sending them to a Ukrainian citizen (…) an employee of an aircraft factory in the southern Ukrainian city of Odessa.

The press release pointed out that the facts would have happened while he was a technical director of an aircraft factory and had access to classified documents + top secret +. An investigation into “high treason” has been opened, the FSB said, a crime punishable by the harshest prison sentences in Russia. The suspect was arrested.