Thai police are investigating the release of a set of icons on messaging app Line depicting the royal family.
The Japanese company has apologised and withdrawn the virtual stickers which it said were “culturally sensitive”.
Thailand’s strict lese majeste law bans criticism of the king, queen and his successor, but has been broadly applied to references to the monarchy. It carries a maximum 15-year jail term.
Critics say the law has been used to silence discussion about the royals.
Line is one of the most popular messaging apps in Asia.
Suppaset Chokechai, commander of the police technology crime suppression division, confirmed the investigation with the BBC but declined to give any more information on the case.
The stickers depicted various members of the family, including the revered King Bhumibol Adulyadej and his children, and appeared to reference rumours about them.
But some stickers also feature known facts about them, such as the king’s fondness for the saxophone and Crown Prince Maha Vajiralongkorn’s deceased pet dog.
The set appeared to have been submitted to a section of Line’s online shop where users can sell stickers to others. Line reviews submissions before they are put on sale.
Line issued a statement on Thursday saying it had withdrawn the stickers, saying they “may have caused discomfort among our users in Thailand”.
It added that it would continue to improve its processes and “consider cultural aspects of each country”.
Thailand has seen an increased spate of arrests under lese majeste in recent years, some under broad interpretations of the law.
Since its coup in 2014, the military government has used the law to arrest a string of suspects accused of claiming or using connections to the monarchy for personal benefit.