JAKARTA - Singapore's Immigration & Checkpoints Authority (ICA) on Tuesday (Dec 27) deported an Indonesian man and woman who allegedly had plans to travel to Syria to join the Islamic State of Iraq and Syria (ISIS). Both were deported to Batam.

The man was a 40-year-old native of Medan, North Sumatra province, identified only as MNA. The woman, also 40, was identified only as SI and is known to have resided in West Java province.

Both had reached HarbourFront Centre in Singapore on Monday (Dec 26), and were held for interrogation before they were deported the next day, said Lieutenant Colonel Saprono Erlangga, the Riau Islands police spokesman.

The couple had left Batam on a Queens Star speed boat on Monday afternoon. They had planned to continue their trip to Syria after Singapore.

"They are now under interrogation with police and immigration officers. They planned to go to Syria. Investigation is being carried out intensively on whether they are planning to join ISIS," Mr Erlangga said.

This is the second reported case of Indonesians planning to travel to Syria by using Singapore as a transit point.

On Feb 21, three staff of a West Java radical Islamic boarding school and a teenage student were stopped in Singapore and sent home.

They were deported to Indonesia after investigations revealed they had plans to make their way to Syria to fight for ISIS, said Singapore's Ministry of Home Affairs two days later. The four were Mukhlis Khoirur Rofiq, 22, his brother, student Muhammad Mufid Murtadho, 15, Risno, 27, and Untung Sugema Mardjuk, 48.

All four were questioned by the police anti-terror unit, but they could not be detained further because, under the country's anti-terror laws, they did not commit any offence.

All were released on Feb 24.