How A Mysterious Tortoise Appeared In Our Backyard Today (Photos)

So, I woke up this morning to find this creature in one of the buckets in the bathroom. My little nephew told me that he found it at our backyard this morning.
We don't know how it got there. Our backyard isn't bushy,neither is our area. Although there's some swampy land behind our compound,and it's possible that the heavy rain that's been falling for the past few weeks could have influenced it's migration to our compound.

The problem now is, we are confused on what to do with it.. My mom is talking about keeping it and raising it,but I don't think that's a good idea. A tortoise isn't an ideal pet in my opinion. We don't even know how to take care of it...
I suggested we sell it to a mini zoo that's located not too far from our area, but I'm not sure they would be willing to buy it.

I'm quite confused on what to do... Your advices would be well appreciated. Thank you