In the past two years, five maids working in Singapore were radicalised, although they “did not pose an imminent security threat” at the time, said the Ministry of Home Affairs (MHA).

 The maids were among some 70 foreigners investigated during that period, and had been radicalised through social media. Some of the foreigners were later deported after the authorities in their home countries were informed of their cases.

 The statement yesterday came after Indonesia’s anti-terror police commandos rounded up four women in the past week on suspicion of terrorism. Among them was Dian Yulia Novi, 27. She had worked in Singapore between 2008 and 2009, said an MHA spokesman.

 Dian had allegedly been planning to mount a suicide bomb attack on the presidential palace in Jakarta. In a television interview broadcast last Tuesday, she said she was first exposed to radical Islam through Facebook by opening profiles of extremists while working as a maid abroad.

 She worked for a family with three children here, and as a maid for three years in Taiwan.

 …Dr Rohan Gunaratna, head of the International Centre for Political Violence and Terrorism Research, noted that militant group Islamic State in Iraq and Syria is investing heavily in recruiting in cyber space.

 While Singapore has secured its physical space, it “now needs to better protect its citizens and residents, including the labour population, from cyber radicalisation”.