I decided to restart this game (been since August since I played originally) and wanted to go "ghost". To do this, of course, killing wasn't going to be an option.

However, I just got through the very first stage and while I did get ghost, it says I killed one person.

There's no way. I never once drew my blade on a single person and the only dart I fired was definitely sleep (I double-checked before firing it as well as only put sleeping darts in my fast select button).

So... what went wrong?

I'd like to know if anyone has any idea why this section flagged a death.

What did you do with the body of the guard you put to sleep? When you escaped the prison, could any bodies be caught in the explosion?

Prior to setting the charge, I moved all three into the back control room. I'm absolutely positive no one died in the prison.

Unfortunately, I can't think of anyone in the sewers who would have died, aside from those two who get eaten by rats (we can't get to).