WASHINGTON (AP) — A New Jersey man who authorities say was on his way to Ukraine to join a volunteer fighting unit has been arrested in an alleged plot to attack a U.S. electrical substation to advance his white supremacist views, the Justice Department said Thursday.

Andrew Takhistov, 18, was arrested Wednesday at the Newark Liberty International Airport, where he was headed to Paris before going to Ukraine to join the Russian Volunteer Corps, a pro-Ukrainian group fighting Russian forces, officials said.

Authorities say Takhistov began talking in January with the person he did not realize was an undercover agent, and he began discussing a plan to attack an electrical substation. They drove together to two electrical substations in North Brunswick and New Brunswick, New Jersey, and Takhistov provided information on how to construct Molotov cocktails, the type of clothing to wear and where to park to avoid detection, authorities said.