Home Affairs Minister Wong Kan Seng vowed on Sunday that no stone will be left unturned and no effort will be spared in tracking down the Singapore Jemaah Islamiah (JI) militant chief, who is still on the run after nearly five days of extensive land, sea and air search involving more than 1,000 policemen, soldiers and Special Operation Command forces.

The three Committee members appointed to carry out the inquiry are retired High Court judge Goh Joon Seng, now a member of the Council of Presidential Advisors, former Commissioner of Police Tee Tua Ba, who is now Singapore's Ambassador to the United Arab Emirates, and Dr Choong May Ling, Deputy Secretary (Security and Corporate Services) of the Ministry of Home Affairs.

The Committee is expected to complete the inquiry and submit its report within a month.

Separately, the Criminal Investigation Department will hold an internal inquiry to determine if there is any criminal wrongdoing.

Mr Wong, who is Deputy Prime Minister, said there was a 'physical breach' at the Whitley Road detention centre that led to the terrorist's breakout, and this had been dealt with. Security within the detention centre had also been beefed up.

Asked to elaborate on the 'physical breach', he said: 'You will have to wait until the investigation is over.'

Pressed further on whether the breach was part of the structure at the detention centre, Mr Wong replied: 'You will know that later on.'

He would not give further details.

Mas Selamat, 47, who once plotted to hijack a plane and crash it into Changi Airport, had been detained since 2006 under the Internal Security Act.

Mr Wong said the Committee of Inquiry would be thorough in its probe 'so that we can get an objective, balanced and comprehensive report on what took place and what we must do'.

On the Committee members, Mr Wong said Mr Goh, who retired from the Supreme Court in 2000 after serving for almost 10 years, has a very good standing in the community and had contributed to the public service in various capacities since 1970.

Mr Tee, 66, who was the Police Commissioner from 1992 to 1997, 'is experienced and the knowledge he has on police operations will add value to the committee', said the Minister.

Dr Choong started her career in the Ministry of Health and has held various senior positions in different ministries before joining the Home Affairs Ministry in December 2003.

Mr Wong said the escape of the JI leader has dented Singapore's reputation.

'We have a good reputation on safety and security, that has suffered a knock somewhat but I believe our reputation continues to remain high compared to many other countries. And we will do everything possible that this does not happen again,' said the minister, in the first update on the JI fugitive since his statement to Parliament last Thursday.

'But we must not be demoralised by it. We must learn from it because we learn from mistakes so that they will not be repeated. We will recover from it and, hopefully, one day we will find him.'

Asked on what the next strategy would be if Mas Selamat was not found within the next two weeks, Mr Wong said: 'We will have to go as we progress. We have to see the development and see what more we can do to enhance our efforts.'

'But after searching the whole of Singapore and every lead and every possible haunt that he may be found, we will have to find a way to find him through other means.'

On whether the Government would offer a reward for Mas Selamat's arrest, the minister said: 'This is not the practice of the police.'

Mr Wong said he is heartened by the overwhelming support from members of the public in the hunt for the JI fugitive.

He also commended the police and military search forces who have been working round the clock to track down the runaway militant, and their supportive families.

'I just spoke to the Special Operations Command officers. Their spirits and morale are high. They are dedicated in their jobs,' said Mr Wong.

'Their families and the families of the other officers really support them in their efforts. Some of them have to make alternative childcare arrangements. You can see the whole home-team effort is on it (finding the escapee).'

Grassroots leaders, Malay community leaders, students and scores of others have been helping to distribute police fliers on the wanted man at various places in Singapore, such as town centres, MRT station and bus interchanges.

On popular social networking site Facebook, about 200 people have joined five groups in the hunt, by putting up pictures and news articles of Mas Selamat and holding forum discussions.

The public are also giving leads to police, who have received about 300 calls so far providing information.