yes i saw it eat it, I saw the star fish being pulled in to a hole in a rock so i picked up the rock to have a look and there it was,the star fish was alive not long before thatIt looks like a bad worm that I have caught and disposed of before.
I'd be surprised if it did not have pincers in it's mouth.
It actually looks like the blood worms I use to sell whilst working in a fishing tackle shop (awesome bait).
Did you actually see it eating a starfish? Was the starfish already dead?
no I am not putting it back in, it is a ugly looking thing, hope there are no more, i have other star fish and feather duster worms that a re doing real wellIt looks different to the common bristle worms most of us have. I would not put it back in the tank just in case and considering you found it eating one of your inverts.