lawn tractor blades stopped turning

Hi,
I have a Craftsman YT3000 and I hit a log with it and then the blades started making a funny noise so I stopped the mower and had a look. The blades looked fine and all of the belts looked good. I was able to manually turn both of the blades using the cog that comes from the engine.
Then I started mowing again and while it sounded a little funny, it was mowing okay. Then the blades started to sputter and then they both stopped. Anyone have an idea of what could be wrong?
Thank you

remove deck & inspect all parts topside & underside, belts, blades, pulleys, hardware, etc. let us know what you find, thanks.