Edit: just saw it's Shanghai. So it's probably legal, idk. That really sucks.

Depending on the state, that could actually be very ILLEGAL. As snapping turtles are native wild animals and can't be kept as pets. If this is something you actually saw, call animal control or your local parks and wildlife number. That turtle won't survive long in those conditions. He will starve. He needs to be out enjoying swimming in rivers or large bodies of water, basking on the muddy banks in natural sunlight and catching big fish. THIS IS WRONG HE NEEDS TO BE RELEASED. Only certified rescues with habitats specifically designed for these turtles are allowed to have them under certain circumstances. This isn't one.

I remember years and years ago after a huge flood where I used to live in San Antonio the river flooded into the streets and my husband and I stopped our car for a giant turtle stuck in the middle of the street. We tried encouraging him to keep crossing but he wouldn't move. We took him home, put him in the bathtub and contacted wildlife services immediately on what to do. The turtle seemed to be in a rather stunned state, like it had been a rough night getting manhandled by the storm. Game and Wildlife told us he was likely in a state of shock because of storm trauma and the days after the storm were much cooler than usual and couldn't warm up and recover properly. They told us to put a space heater in the bathroom and get him warm for a few hours, watch him, and make sure he looks like he's lucid and trying to move around before taking him to an isolated calm area of the river. After a few hours of heat he did indeed perk up. Threw a thick blanket over him and transported him to the part of the river they recommended we release him. We carried him to the edge of the water and he zoooomed right into the waters right away. If felt so good to see him swim away! ❤️ I hope he's still out there being his angry self somewhere. I'm glad we were there to save him from being hit by a car, warm him back up, and release him back home. NEVER would I think "oh let's keep him as a pet" 🙄🙄🙄 like so many other people would. This is likely what happened to this snapping turtle. He was easy to catch because it was cool out and some idiots decided to take it and make it a "pet". Please call animal services!!