The State Security General Ivan Alexandrovich Serov (13 August 1905 – 1 July 1990) was a first head of the KGB between March 1954 and December 1958. Serov was also the head of the GRU between 1958 and 1963.
Serov was removed from his post as head of the KGB in 1958 after a few hints by Nikita Khrushchev. Khrushchev had said that Western visitors could expect that they "wouldn't see so many policemen around the place" and that the Soviet police force would need to undergo a restructuring.
Under Lavrentiy Beria, he was the Deputy Commissar of the NKVD. He played a large role in the power struggle after Joseph Stalin died. Serov helped establish a variety of secret police forces in Central and Eastern Europe after the lowering of the Iron Curtain. He played an important role in crushing the Hungarian Revolution of 1956.
He headed both the KGB and the GRU, making him a unique figure in Soviet/Russian history. Inside the Soviet security forces, he was well known for showing off to his colleagues that he could "break every bone in a man's body without killing him".
There is possibility that he shot Nikolai Yezhov.