Former national security adviser John Bolton compared Kash Patel, President-elect Trump’s nominee to head the FBI, to one of the former Soviet Union’s most feared secret police chiefs, Lavrentiy Beria.

“Trump has nominated Kash Patel to be his Lavrentiy Beria,” Bolton said in a statement to NBC News’s “Meet The Press” on Sunday. “Fortunately, the FBI is not the NKVD. The Senate should reject this nomination 100-0.”

NKVD refers to the interior ministry and secret police of the Soviet Union, which was in place from 1934 to 1946.

Beria was appointed by former Soviet Union Prime Minister Joseph Stalin as deputy chief of the Soviet secret police and was head of the Soviet atomic bomb project, according to the Atomic Heritage Foundation. He is known for his violent tactics, including kidnapping, torture and rape, which he used to advance within the ranks of the secret police. At the time, Soviet leaders reportedly feared that Beria would use his control of the secret police to fully seize power.

Beria was later tried and convicted of treason and was executed in Moscow in 1953.

—Updated at 12:59 P.M.