THERE was a "physical breach" at the Whitley Road detention centre that led to the escape of Jemaah Islamiyah (JI) terrorist Mas Salamat Kastari last Wednesday.
Security within the detention centre has since been beefed up.
The breach was revealed to reporters by Deputy Prime Minister and Minister for Home Affairs Wong Kan Seng yesterday during his visit to the Special Operations Command's (SOC) Queensway base.
The media was also given its first official update sinceMas Selamat's escape, The Straits Times reported.
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."
The chief of the Singapore JI chapter is still believed to be in Singapore, Mr Wong said.
The 47-year-old fugitive is also believed to have escaped unaided, the police added.
Said Police Assistant Commissioner Wong Hong Kuan at the media briefing:
"When he escaped on Wednesday, we believe he was unaided, and therefore he does not have access to money, vehicles, modes of transport.
"That underpins our belief that he is still in the country. That's why we're conducting a very intensive search."
He added: "But we are taking nothing for granted in terms of where might be. We don't want to have any preconception or bias of what his intentions might be. In that sense, we are leaving no stone unturned in our pursuit of him."
AC Wong also said that the public was not told about the escape on Wednesday evening until about four hours after in order to avoid causing panic.
He said: "Our focus in the first few hours was to ensure that all these were done.
"It was a decision taken that we need to be sure of the parameters and what is actually happening before we give out information to the public.
"If we just give out information that he is out there, it may cause public panic.
"The issue is more about what sort of credible infomation you can give to the public so they can help police in our search effort in a very short span of time."
It was also revealed that about an hour after the escape, the manager of a petrol kiosk on Whitley Road said he saw a man resembling Mas Selamat limping up a flight of steps on a hill slope near Malcom Park, leading to the Bukit Brown Chinese cemetery.
This prompted the police and security forces to set up a huge cordon around the area and an intensive search. The hunt was called off after two days and moved to other areas.
"At that point, we had credible info that he was in the Malcom Road area and the priority then was to conduct the search," said AC Wong.
The police said that while on the run, Mas Selamat would be in need of food and money, and is likely to try to conceal his identity".
That's why, police warned, the fugitive "could resort to stealing items like clothes and food to get by".
The authorities also added that the limp in Mas Selamat's left leg is not pronounced when he is walking. It shows up only when he is running or walking fast.
Police asked the public to look out for the fugitive who could be wearing stolen "ill-fitting clothes or a cap".