It has been more than a month since police vowed in late January they would arrest the serial rapist of 10 women — nine of them elderly — within two weeks.
The rapist has been at large since his first attack on a 70-year-old woman in Samut Sakhon in September, 2010. Two of his 10 suspected victims were murdered.
Police have issued Identikit sketches of the suspect, and obtained DNA samples confirming the rapes were committed by the same perpetrator.
Apart from that, little progress has been made to help police identify the culprit or come closer to finding him. Police are now worried the trail is going cold.
As there appear to be no new clues around the corner, police have decided to look back at their past work and re-examine the evidence they have collected so far.
"I admit this case is difficult because the rapist left no crucial clues," Central Investigation Bureau (CIB) acting chief Thitirat Nonghanpitak told the Bangkok Post over the weekend.
But that does not mean police will give up, Pol Maj Gen Thitirat said, insisting officers must bring him to justice.
Thitirat: Evidence to be re-examined
The CIB will meet local police this month to plan a new approach to investigations, he said.
It is possible that some of the evidence is flawed, which could be hampering the inquiry.
There are few witnesses to the rapes and murders, which occurred in Nakhon Pathom, Samut Songkhram and Samut Sakhon.
In many cases, the victims and witnesses are the same people, Pol Maj Gen Thitirat said.
"The victims are elderly. They were shocked by the attacks and don't remember many important details about the rapist," he said.
"Some clues might be inaccurate and we don't have any key evidence or security camera footage because attacks occurred in their gardens and homes."
One major piece of evidence the police do have is the suspect's DNA.
It was collected from all victims, including the two women who were killed when they resisted his attempts to rape them.
Other clues seem to offer little help to the investigation.
Police found bottles of rice whisky at some of the crime scenes.
Unfortunately, there were no traceable fingerprints or DNA on the bottles.
Investigators discovered a fingerprint on the window of one victim's house, but officers have not been able to confirm whether it belongs to the rapist.
While the evidence is limited, police have many questions about the case: How did the rapist know his victims lived alone? Why did he always choose houses near canals?
"What police want to know most of all is how he found his victims, how he chose them," Pol Maj Gen Thitirat said. (story continues below)
These Identikit sketches of the suspect made from survivors' descriptions have been no help in the case.
Investigators also want to know whether the rapist travelled to victims' houses by boat or car.
Earlier, police thought the suspect was a labourer due to victims' accounts that he is well-built and strong. But officers do not think so now.
"The rapist could be anyone," Pol Maj Gen Thitirat said.
The suspect could be a postman or a tambon organisation administration official, he added.
Due to the many unanswered questions, the CIB must re-investigate the case, he said.
The CIB chief recently had 5,000 leaflets with the rapist's details distributed to people in the three provinces where the attacks took place.
Each leaflet showed three composite sketches of the rapist with details of his physical appearance. He was described as aged between 35 and 45 years old, with dark skin and often wearing a hat or cap.
The leaflet also contains information on the suspects' 10 attacks. Most of the women were elderly — with the oldest being 78.
However, one victim was a 37-year-old Samut Songkhram resident. She was a victim of an attempted rape and assault.
A 61-year-old victim in Samut Songkhram and 78-year-old victim from Nakhon Pathom were killed by the rapist.
The latest victim was a 70-year-old woman in Nakhon Pathom's Nakhon Chaisi district who was raped on Jan 25.
No new rape cases have been reported since.
Pol Maj Gen Thitirat's subordinates are keeping a lookout at risk areas, hoping to collar the culprit or find clues that will lead to his capture.
Contact Crime Track: crimetrack@bangkokpost.co.th