which incident were there more deaths? the Nanjing Massacre? or Hiroshima and Nagasaki atomic bombing death toll combined?

reason for asking this question, is due to the bad blood, resentment, bitterness between China and Japan, well mainly on China's side, China feels that Japan has never held themselves accountable for the war crimes they have committed against China, that Japan has never apologized for the atrocities, crimes against China during the Sino-Japan wars.

The main source of friction, resentment, is the Nanjing Massacre, the death toll seems to vary but its often estimated at like 300,000 people killed, or less than that, or more.

With the Atomic bombings of Hiroshima and Nagasaki, I've heard over 200,000 people were killed in both total, or less than that, but I've heard varying stats for both.

i'm bringing up both incidents, because I assume China views the atomic bombs of Hiroshima and Nagasaki, as karma, revenge, payback for the Nanjing massacre.