My White LT185 riding lawn mower has a oil leak coming from the front of the engine block, what could it be?

Last week, just as I was finishing up my yard, the engine began to pop, but nothing seemed to change performance wise. I put the mower up in the garage and this week when I went out to the garage, I found a large puddle of oil underneath it. It will start but oil is coming out rapidly. The mower is not that old and I keep the oil changed, this seems odd that it would just let go.My White LT185 riding lawn mower has a oil leak coming from the front of the engine block, what could it be?
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