Twenty-three people, including women and children, were arrested by Selangor Islamic Religious Department (JAIS) officers at a Shia center at Gombak, Malaysia, Friday night.
The 25 officers went to the center at about 9.45pm and arrested the 23, who included four boys aged 13 to 17, sources said.
They were holding mourning rituals marking the anniversary of the martyrdom of Imam Hussein, peace be upon him, the third Shia Imam.
Those arrested were brought to the Islamic complex at Gombak and were told that they were being investigated under shariah law for opposing the fatwa on the practice of Shia Islam, the sources told Free Malaysia Today.
The minority Shia community in Sunni Muslim-majority Malaysia has been subject to discrimination and persecution by authorities, human rights groups have said.