In discussing what King Herod had heard about Jesus, in Mark 6:16-17, it says:

But when Herod heard this, he said, “John, whom I beheaded, has been raised from the dead!” For Herod himself had given orders to have John arrested, and he had him bound and put in prison.

If you continue reading verse 14 through verse 29, it's clear that Herod knows John is still in prison. In fact, he doesn't behead him until verses 27-28. Why would he then say he had been raised from the dead knowing he is still alive?

All I could come up with is that this sequence is not in chronological order. Are verses 14-16 the result of what happens in 16-29?