Wheel Horse 312-8 Lawn Tractor blade does not turn?

Greetings Technicians, I have a Wheel Horse 312-8 Lawn Tractor that I was using today and the blades stopped working but the engine ran fine. It would seem like a belt due to the engine continue to run and no loss of power or speed. The only concern is that white smoke came out of the exhaust. The grass was longer than normal. Any ideas? It was getting dark so I didn’t see a belt, I’ll have to look in the am.
Any help or ideas would be great. Never fixed a mower before.. the blades make me a little hesitant.
Thanks, Kacey