A total of 16 men and four women from Indonesia were arrested on Saturday at a palm oil farm near Kuala Lumpur. Police accused them of allegedly having illegal affiliations to an Indonesian martial arts organization and conducting religious activities which violate Malaysian Islamic law.

After receiving citizens’ reports of groups of people seen acting suspiciously at a palm oil farm in Tanjung Sepat, Bagan Lalang, officers raided the location on October 20, the China Press reported.

The suspects were believed to be affiliated to an illegal organization called Ikatan Keluarga Silat Putra Indonesia Kera Sakti, as they were found practicing martial arts underneath a banner of the organisation.

They were also in the middle of acts of worship over offerings including yellow glutinous rice, fruits and roasted animals.

Of the 20 arrested, 11 were detained for not having valid travel documents.

The case is now being investigated under the Immigration Act 1959/63 and the Societies Act 1966 on suspicion of involvement with illegal organizations and of engaging in deviant practices based on looted goods.