Cartoonist Zunar and four others were detained during a police raid at an event in Kuala Lumpur on Saturday.
Police have also seized books and merchandise at the “Tea With Zunar” event held at the Kuala Lumpur-Selangor Chinese Assembly Hall.
All five were taken to the Dang Wangi police district headquarters for questioning.
The reason for arrest was not known.
The Star reported that Dang Wangi OCPD ACP Mohd Sukri Kaman had confirmed the arrest.
Zunar, 54, real name is Zulkiflee SM Anwarul Haque.