Police are seeking help from Interpol to hunt the suspected Erawan shrine and Sathon pier bombings mastermind who they believe has fled to Bangladesh.
Deputy national police chief Chakthip Chaijinda, who leads the investigation into the bombings, Wednesday said Abudureheman Abudusataer, known as Ishan, is believed to be the head of the network which caused the deadly bomb blast at the shrine on Aug 17, based on the accounts of the detained suspects.
Interpol will be asked to contact Bangladeshi authorities following reports that Ishan had fled to the country, he said.
An investigation is underway to look into money wired from overseas to determine whether it was used to sponsor the attack, he said.
Pol Gen Chakthip said he is confident police will be able to arrest the yellow-shirted man, who was seen in CCTV footage planting the bomb-laden backpack at the shrine, based on evidence he gathered.
Full graphic of The Bomb Trail below
Meanwhile, a source said investigations found Mr Ishan had sent an audio clip via Facebook to other suspects containing the screaming voice of a woman whom he claimed was a Uighur and was being deported from Thailand to China.
He met four other key suspects in Thailand. They are Yusufu Mieraili; Bilal Mohammed, also known as Adem Karadag; a man wearing a blue shirt who dropped a bomb into the river at Sathon pier, and the man in a yellow shirt who is believed to be the Erawan shrine bomber.
There is still another suspect living overseas who sponsored the attack, the source said, adding the person booked air tickets en route to Turkey for the suspects. Money was wired to the bank accounts of some suspects, the source said.
Investigators said earlier Mr Mieraili said Mr Ishan had arranged meetings of the bombing cell and assigned them their tasks.
Police sources said the warrant for the arrest of Mr Ishan was issued on Tuesday but police later decided to rescind it as more investigation was needed to ensure stronger evidence.
National police spokesman Prawut Thavornsiri said information about Mr Ishan has been shared with Interpol to help check his records.
According to the spokesman, the bomb used in the attack was unusual and seldom seen elsewhere.
However, some bomb-making materials, including fuses, can be acquired in Thailand.
The National Council for Peace and Order called on fertiliser and chemical substance shops to install CCTV.
Pol Lt Gen Prawut insisted more than 10 people were involved in the bombing network.
More Thais -- apart from Wanna Suansan, who rented a room at the Maimuna Garden Home apartments in Bangkok's Min Buri district where urea-based fertiliser and other bomb-making materials were discovered -- could have been involved, he said.
Police on Wednesday took Mr Mieraili to re-enact his alleged criminal acts at several places, including a plaza in front of CentralWorld shopping centre and Hua Lamphong railway station.
Pol Lt Gen Prawut said Mr Mieraili told investigators that he carried the backpack weighing 3-4kg. Mr Mieraili said he did not know what the items in it were but suspected that it might have been a bomb. He carried it from Nong Chok district to the train station and handed it to the yellow-shirted man.
The spokesman said Mr Mieraili then took a tuk-tuk to Wat Pathum Wanaram, from where he walked to CentralWorld to take photos of the blast scene in accordance with orders.
Due to a pillar blocking the scene, the suspect did not take photos and headed to the Pratunam area and fled, Pol Lt Gen Prawut said.
The spokesman said Mr Mieraili had not admitted to assembling the bomb, but he said he only took explosive substances to Room 414 of the Pool Anant apartments in Nong Chok district.
The suspect claimed he did not know both the men wearing yellow and blue shirts, Pol Lt Gen Prawut said.
Mr Mieraili also claimed he did not know the motive for the attack as he was "just following orders".
Police also took Mr Mieraili to Bangkok Bank, Soi Ramkhamhaeng 22, for a crime re-enactment.
The investigation found that he and Mr Ishan went to the bank on Aug 5 to conduct transactions, the police source said.
Police then took the suspect to the Min Buri Provincial Court to seek his detention for 12 days.
National police chief Somyot Poompunmuang said prosecutors will consider which court will indict the suspects. No decision has been made at this stage, he said.
He insisted the case was not being treated as international terrorism, which must involve organisations.
Deputy Prime Minister Wissanu Krea-ngam said the bomb suspects could be tried in the military court.
The National Council for Peace and Order (NCPO) earlier announced four offences can lead to suspects being tried in the military court. They are violations of Section 112 of the Criminal Code, known as lese majeste law, the Firearms Act, NCPO orders and security affairs.
Mr Wissanu said the trial process in the military court would be faster as there were not as many cases being heard there compared with civilian courts.
"The deliberation and witness inquiry would be quicker than the cases entering the normal process of lawsuits," Mr Wissanu said.
Yaowalak Anuphan, head of the Thai Lawyers for Human Rights (TLHR) centre, said the organisation sent a representative to observe judicial proceedings last Saturday, as the Min Buri court approved a police request to detain the suspect, Mr Mohammed, for 12 more days.
Mr Mohammed reportedly had no legal representation and no interpreter as he faced the court. The suspect is being remanded at Min Buri prison.
The TLHR centre has been in touch with the Muslim Attorney Centre Foundation to arrange a lawyer to represent the suspects.
Pol Gen Somyot said the Lawyers Council of Thailand could provide lawyers for the suspect.
At Government House, Prime Minister Prayut Chan-o-cha said the Foreign Ministry will work with the Thai embassy in Turkey to take care of Thais amid recent protests.
The move comes after ethnic Kurds ramped up protests in numerous Turkish cities.
Several homes occupied by Thais in Alanya have been affected in the unrest.
