Singapore's Ministry of Home Affairs said Friday it has detained an Australia-based national over allegations that the individual "glorified" the Takfiri Daesh terrorist group.
Zulfikar Mohamad Shariff is being held under the Internal Security Act (ISA), the ministry said in a statement.
The act allows for detention without trial of individuals for being a threat to Singapore's national security.
"Zulfikar has made use of social media to propagate and spread his radical messages," the ministry said.
The 44-year-old, the statement added, posted messages on Facebook that also radicalized two Singaporeans, a businessman and a security guard.
The ministry said in Australia, Zulfikar joined a hardline group while making "numerous Facebook postings glorifying and promoting ISIS (Daesh)."
He had also supported other terrorist groups such as al-Qaeda and its Southeast Asian affiliate Jemaah Islamiyah, the ministry added.
The statement further said the detained man encourages violence.
"In view of the high level of terrorism threat that Singapore currently faces, and the global terrorism threat posed by ISIS, Zulfikar's promotion of violence and ISIS and his radicalizing influence pose a security threat to Singapore," the statement said.
The ideology of Daesh is largely influenced by Wahhabism, the radical ideology dominating Saudi Arabia and freely preached by Saudi scholars.