What does 2 Kings 10:9 mean?

The next morning, Jehu went out and stood before the people. He said, 'You’re innocent in all this. I’m the one who rebelled against my master and killed him, but who killed all these? 2 Kings 10:9 - Modern Text Bible

(Jehu distances the people from the massacre, claiming responsibility for killing the king but pointing out that others killed Ahab’s sons.)