The apparent death of the man known as "Jihadi John," the public face of the self-styled Islamic State, may represent a kind of karma but it doesn't bring closure for the father of one Japanese hostage beheaded nearly a year ago.

"It's not to say that it was heaven's punishment doing its work, but what you do to other people will come back to you," Shoichi Yukawa said Saturday of the U.S. announcement that it was "reasonably certain" it had killed Kuwaiti-born Briton Mohammed Emwazi, described as the group's "lead executioner."

Yukawa, 75, speaking at his home an hour east of Tokyo, chose his words as he reflected on the death of the man who murdered his son, Haruna, who was apparently beheaded in January after several months in the hands of the Islamic State group in Syria.