A park in Thailand has got so fed up of people dumping their rubbish there that they have sent a clear warning.
Khao Yai National Park near Bangkok will start sending rubbish back to litterers, Thailand's environment minister said.
Anyone who visits the park will have to register with their addresses, making it easy for rangers to track them down if they leave rubbish behind.
Littering is already against the law in Thailand, but these new rules with make it easier for the police to find who is making such a mess!
Khao Yai National Park is the oldest national park in Thailand and known for its waterfalls, animals and scenery.
Environment Minister Varawut Silpa-archa posted pictures of the mess left behind at the park with the message:
"Your trash - we'll send it back to you"
Now that's some junk mail, none of us would want!
But what do you think? Is posting someone's rubbish back to them a good idea? Take a vote and tell us why in the comments.
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