Biological Weapons used in Korean War

From "Codename Artichoke", a film by Egmont R. Koch and Michael Wech: Dr. Frank Olson (also army captain and CIA agent) was probably pushed to his death by a fellow CIA agent in late 1953. He was involved with biological weapons and torture (project Artichoke). It is claimed in the movie that biological weapons were used in the Korean War.

Norman Cournoyer, friend and coworker of Frank Olson talks with Eric Olson, son of Frank Olson, on the topic of biological weapons used in the Korean War.
Norman: "I took an oath when I left the United States army that I would never divulge that type of stuff."
Eric: "Well you divulged it to me."
Norman: "You can't prove it can you?"
Eric: "I can.. I can assert it--you told me."
Norman: "Hearsay."
Eric: "So you dont want to say it."
Norman: "No I dont want to say it, but, there were people who had biological weapons and they used them. I won't say any more than that--they used them.... Was there a reason for your dad being killed by the CIA? Probably so."

Eric Olson on the death of his father, Frank Olson:
"What this means for me is that in National Security, homicide is not only a possibility, but really it's a necessity, when you have a cerrtain number of ingredients together. If you're doing top-secret work that is immoral, arguably immoral, especially in a post-Nuremburg period, and arguably illegal and at odds with the kind of high moral position that you're trying to maintain in the world, you have to have a mechanism of security which is going to include murder."