Like their counterparts in Singapore and Taiwan, the Sio Sam Ong mostly consists of the Hokkien ethnic group.
In Malaysia, they were actively involved in politics by joining the government coalition (Barisan Nasional) parties United Malays National Organisation (UMNO) and the Malaysian Chinese Association (MCA) to cover up their identity.
[3] According to Penang police, the triad has been involved in international drug trafficking, kidnapping, murder, extortion, racketeering and loansharking at its height.
[citation needed] Sio Sam Ong members were also suspected of involvement in at least 10 murders in the Penang in the late 1980s and early 1990s, including a notorious massacre at pre-wedding celebration in the Sungai Petani district of Kedah in September 1992, where six people where shot to death.
[4][5] In December of the same year, five skeletal remains with their hands tied behind their backs, believed to be Sio Sam Ong members who betrayed the gang, were exhumed from unmarked graves in Mount Erskine, Penang.