Lavrentii Beria's son Sergo -- still alive in Russia, by the way, and a
scientist of repute himself -- published a book titled My Father,
Lavrentii Beria. In it he tells how a young American scientist named
Robert had dinner with the Beria family once in 1939. Sergo B. goes on
to say that in 1942 or 1943 heard from one or two Soviet government
ministers about the US project to build the A-bomb and that it was
headed by a man named Robert Oppenheimer. He asked his father if this
were the same Robert who had had dinner with them, and Beria said it was.