Maggots killing a lizard and eating it?

I was doing an experiment. I had an already dead lizard in a jar, being eaten by maggots. Then I put in a live lizard into the jar. An hour or so later the maggots were all over the live lizard trying to burrow into it while the lizard was still alive and active. A few hours later the lizard is dead and the maggots are inside of it. This is weird. Aren't maggots supposed to only eat dead and decomposing tissue? Is it because the lizard was around the rotting juices and it confused the maggots? Someone explain.