Singapore's government says it has been holding two of its citizens since August for attempting to make their way to Syria to join the Islamic State group.

The Ministry of Home Affairs said in a statement Wednesday that Muhammad Shamin Mohamed Sidek, 29, and Muhammad Harith Jailani, 18, were detained without trial under the country's Internal Security Act in separate cases.

The announcement of the arrests comes amid growing concern that more youths in the region are being radicalized by the Islamic State group and volunteering as foreign fighters, with countries in the area tightening security checks.