That is no surprise at all. But ruthless men did not have to come from the KGB. They were everywhere, and the most ruthless rose to the top.
I recall reading was he was very high up at the KGB and alot of KGB officials in Russia went into in hiding during Yeltsin period when ordinary people were seeking revenge for dead family members but since he did all dirty work in Germany he was not disliked by the Yeltsin camp.
So he was like the last man standing at the KGB that had no Moscow enemies but Yeltsin needed him to attract some of the old guard from creating a civil war.
What a mistake by Yeltsin and his camp.