Mindhunter on Netflix

I was about 10 when the murders in atlanta happened. I've always thought there might have been another killer. I was little and recall a conversation that a couple of the kids were handicap. That doesn't fit the profile so if that's true then I believe there is more than one murderer. Does anyone recall this..
i did not remember it
potentially a few killers but it is noted that the murders stopped once ol boy went to prison