Two Singaporeans planning to travel to Syria to join the Islamic State in Iraq and Syria (ISIS) terror group were detained under the Internal Security Act (ISA) this month.
Rosli Hamzah, 50, a car washer, and Mohamed Omar Mahadi, 33, a waste truck driver, received two- year detention orders, the Ministry of Home Affairs (MHA) said.
In a statement yesterday, MHA also said two Singaporeans have been placed under Restriction Orders, which curtail their movements and activities.
One of them is Omar's wife, Dian Faezah Ismail, 34, the first woman to be dealt with under the ISA for terror activity in recent years.
The ministry said the two detained men had sought information online on how to travel to Syria to fight for ISIS.
"There is growing concern that ISIS propaganda has led to an increase in the rate of Singaporeans being radicalised," MHA said.
Between 2007 and 2014, five citizens were detained and six placed on Restriction Orders. But since January last year, eight citizens have been detained and five placed on Restriction Orders.
Rosli searched for possible travel routes to Syria, while Omar contacted militants for travel advice.
One of the militants was from a South-east Asian country and was later killed in combat in Syria, the ministry said without elaborating.
Both Rosli and Omar became radicalised after listening to Radio HangFM, a Batam-based religious radio station that features speakers who preach extreme views.
Rosli began listening to the station in 2009, and was introduced to ISIS propaganda in 2014 by "social media contacts who shared his religious orientation", MHA said.
He became convinced that ISIS militants were fighting for Islam, and their beheading of 'enemies' was religiously permissible.
"Rosli was prepared to die for the ISIS cause," MHA said.
He was stopped for investigation last month when he returned from Batam after visiting his Indonesian wife and children, and was arrested.
As for Omar, he started to listen to the same station in 2010, and came across propaganda by radical Al-Qaeda ideologue Anwar al-Awlaki in 2012. It led him to read more radical materials online, including from ISIS, and he became a believer of ISIS' warped ideology.
"By 2014, Omar was convinced that ISIS was fighting to bring glory to Islam, and that it was his religious duty to become an ISIS fighter in Syria," MHA said. "He was prepared to die a martyr."
Omar's wife, like her husband, came to believe the terror group's violent actions were legitimate, and helped him in his plans to relocate their family to Syria.
There is no evidence at this point that their children were radicalised, the ministry said. Dian has moderated her views and will undergo religious counselling, it said.
Also placed on Restriction Order is Mohamad Reiney Noor Mohd, 26, a building technician related to Dian and Omar by marriage. He decided in 2013 to adopt a more fundamentalist form of religious practice, and in 2014 came across radical ISIS-related material online.
After viewing ISIS propaganda, he aspired to fight for it and was prepared to die in battle. He also intended to take his family to Syria, MHA said.
But his views about ISIS were moderated after he read negative reports about the group.
"He has also set aside the intention to travel to Syria to join ISIS after he was admonished by a close relative that it was 'forbidden' for him to do so because the fighting in Syria did not concern him and he would be placing his family in harm's way," MHA said.
Reiney will also undergo religious counselling, it added.
There are now 18 Singaporeans and four Bangladesh nationals on Detention Orders, and 24 Singaporeans on Restriction Orders.
Environment and Water Resources Minister Masagos Zulkifli said in a Facebook post that renowned Muslim scholars had refuted ISIS' teachings, "yet their tentacles are long and devious enough to reach our peaceful society". "Support us as we fight this scourge," he added.