Randome killing on my bukkit server

So I have no idea what is going on but every once in a while everyone randomly is killed by "@" which means console. I am the owner and i'm not doing it. No admins are on so they aren't doing it. The only thing I can think of is there is some command block that is doing it. Now my question is how can I fix this without disabling command blocks? Or is this something that happens to people. I was wondering if anyone knows a fix to this specific problem and if not how do you delete all command blocks in the world?

Thanks!

Spark8000