He has been trying to exert his influence over conservative Muslim groups by advocating anti-Chinese and anti-communist rhetoric.
But Islamic scholar Bachtiar Nasir was never able to leave the shadow of Islamic Defenders Front (FPI) chief Rizieq Shihab.
Mr Rizieq had stolen the limelight after leading several street protests against outgoing Jakarta governor Basuki Tjahaja Purnama.
The FPI is part of the National Movement to Safeguard the Fatwas of the Indonesian Ulemas Council, which Mr Bachtiar had formed as an umbrella organisation, to oust Basuki.
Mr Bachtiar used to host a religious TV show until it was cancelled, allegedly after it was revealed that he had played a key role in the rallies against Basuki.
In February, Mr Bachtiar was charged by the police with laundering money purportedly to fund activities linked to the Islamic State in Iraq and Syria (ISIS).
A graduate in Islamic law from Saudi Arabia's University of Medina, he was reportedly among a few Indonesian scholars who used apocalyptic themes to persuade young Muslims to join the war in Syria.
Indonesian police last Thursday confirmed that investigations against the 49-year-old are ongoing.
Mr Rizieq is also under investigation for blasphemy against Christianity and spreading pornography.
The hardline cleric has failed to turn up for further questioning and is now on a pilgrimage in Saudi Arabia. Wahyudi Soeriaatmadja