The Interior Ministry has said that anyone caught using fireworks, firecrackers or other prohibited items during Loy Krathong faces up to three years in prison and a 60,000-baht fine.
Government spokesman Sansern Kaewkamnerd said Prime Minister Prayut Chan-o-cha has asked the ministry to make sure provincial authorities issue regulations and guidelines to the public.
These rules will be overseen by district chiefs for requests to use fireworks or sky lanterns during the festival, which falls on Friday.
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Lt Gen Sansern said the district chiefs must not approve any use of fireworks or sky lanterns until the guidelines are announced by provincial authorities.
He said authorities must keep an eye on manufacturers and suppliers of fireworks during the festival to ensure their compliance with the law.
Appeals have also been made for people to consider using biodegradable materials for their krathong after the litter issues of previous years.