+1. Doesn't surprise me at all. As mentioned, you need to put fish in the tank that can't fit in their mouths or that have a larger profile to appear not eatable. Don't think that a small fish that swims fast is a safe fish. They have to stop sometimes then, GULP.
Size is the secret to success. I had a single Med/ large Angel in a divided tank with Guppies on the other side of the divider. After a water change, I put too much water back into the tank and one of the guppies made it over the divider and I found my Angel with it in her mouth but not able to swallow it whole. I pulled it out of her mouth and the Angel survived. About a month or so later, the guppies had grown quite a bit ( they were almost adults when the one got eaten) and I needed the divider for another tank so the Angel and guppies were now together. Final result, NOTHING.
NO chasing, no biting no going after the Guppies. Did she learn her lesson? Who knows. lol But it goes to show you that their first response is to try and eat what fits in their mouths ( even if it's a little too big. 
) 
) but that doesn't work 100% of the time. Hunger plays a strong influence on that situation. One of my ex business partners raised some Discus in a tank with 100 cardinal tetras. He said that it was a sight to see when the school of cardinals would swarm over the discus as they went from one place to the other in the tank. They were together for over a year with no predation. He had to go away for the weekend and thought it fine to just put some live worms in a cone feeder to feed the fish while he was away. He said when he returned, just 3 days later, almost 1/2 of the cardinals were gone. Guess there wasn't enough worms for them.
It's a common method to raise small Angels with the likes of smaller fish to have them think of the other fish as "friends, not food" ( Sorry, watched Nemo the other day
In your case, the fish in the tank may have been "safe" but did you try to add other smaller fish after the Angel(s) were large enough to eat them? Just curious how that went.
Loooved as in "buddy buddy" or looved as in "please pass the cocktail sauce for us to use on these shrimp"?
