SINGAPORE : Singapore Prime Minister Lee Hsien Loong is confident the country's Internal Security Department (ISD) will prove itself again, especially in light of new security challenges, like those arising from the influx of foreigners into Singapore.

He is also confident that the department will get over the escape of Jemaah Islamiyah detainee, Mas Selamat Kastari.

Mr Lee was speaking at the ISD's 60th anniversary dinner recently.

Singapore's society has become more diverse, with the influx of immigrants, foreign workers and students.

Mr Lee said the ISD will have to be watchful that foreign intelligence agencies do not use this inflow to smuggle in agents, to blend into Singapore's society and be activated later on.

The department will also have to ensure that the foreign communities do not engage in problems of their home countries.

The ISD came under the spotlight in February 2008 when Mas Selamat escaped from the Whitley Road Detention Centre, due to a security lapse.

But Mr Lee said he is confident that ISD is a "competent outfit, well respected by friends and adversaries, even after Mas Selamat's escape." He added that the department "will get over the setback and prove (yourselves) again."

Mr Lee's speech was only released about a week later on Monday, which reflects the undercover role of ISD officers. This point was also mentioned in Mr Lee's speech.

He said ISD officers' identities, once leaked, could also cause harm to their families. However, the officers are willing to take risks for the overall good of the country. - CNA/ms