A police spokesman warned on Friday that acceptable April Fool's Day pranks do not include posting damaging fake news on the internet, which could incur serious penalties.
Pol Col Siriwat Deepor, deputy spokesman, said Fool's Day is a Western tradition involving practical jokes and hoaxes played on friends.
"But sometimes, jokes or hoaxes can affect or shock society when they are posted on social media and shared widely," he said.
People should be careful when taking part, especially if the "fake news" concerns the safety of life and property, national security, terrorism, Covid-19 outbreaks and "other issues that may cause panic or confusion in society".
He warned that posting lies could incur charges of putting false information into a computer system if it was deemed to have caused damage to national security, public safety, economic security or public infrastructures, or made people panic.
"The offence carries a maximum jail term of five years and/or a fine of up to 100,000 baht," Pol Col Siriwat said.