10.Gary Ridgway
Nickname: Green River Killer
Confirmed victims: 49
Suspected victims: 71–90+
Country: United States of America
Status: in prison, life sentence
Gary Ridgway or Green River Killer, named so after the area where first bodies of his victims were found, was sentenced to life in prison for 49 murders, mostly prostitutes. Ridgway himself claims he can’t remember how many did he killed, so the number could be much higher. Even so, he is the most prolific serial killer in the US history.