Thai police are reported to be seeking Malaysian help to identify the source of a mobile phone used in one of the bombings that struck the southern provinces last week.
A portion of a mobile phone used to trigger an explosion in Phuket on Friday contained a Malaysian Communications and Multimedia Commission serial number, according to Bernama news agency.
Thai police, who have not confirmed the report, have gathered closed-circuit television footage and DNA samples from blast sites, and say they expect to make progress in investigations soon.
"Police in region eight have said they might have good news in the next one or two days," deputy national police chief Pongsapat Pongcharoen said yesterday. Region eight refers to the police division overseeing some southern provinces.
Major tourist hot spots as well as central areas in Phuket, Phangnga, Surat Thani, Prachuap Khiri Khan and Trang provinces were hit by a string of explosions over Thursday and Friday.
There were separate arson attacks in Nakhon Si Thammarat and Krabi. Four people were killed and over 30 others, including foreigners, injured.
The toll would have been higher if not for the discovery of two home-made bombs in Phuket on Wednesday which were defused.
General Pongsapat told reporters that the bomb and arson materials in all the sites were similar. "We believe they were done by members of the same group."
The attacks took place on a national holiday to mark the 84th birthday of Queen Sirikit and came barely a week after a controversial draft Constitution was endorsed in a nationwide referendum. Critics had warned beforehand that the draft charter, which expands the power of unelected bodies over elected representatives - and which they argue would entrench military rule - would deepen conflict in the politically riven kingdom.
In a special televison appearance late on Friday night, Prime Minister Prayut Chan-o-cha said the attacks "will serve as a constant reminder to the Thai people that there are some malicious people in our society and in Thailand, who have perpetrated these acts since before our referendum day and now on one of the most important days for our nation".
No one has claimed responsibility for the attacks so far, but suspicion has fallen on the separatist insurgents who are fighting a war against the state in the southern border provinces of Pattani, Yala and Narathiwat, as well as a section of Songkhla.
The long-running conflict in the Malay Muslim-dominated area has killed over 6,000 people so far.
While the insurgents have largely confined their armed campaign to their home provinces, Dr Srisompob Jitpiromsri, a founder of the Deep South Watch which analyses the conflict, said the insurgent network was the only group within Thailand with the organisational capacity to carry out the latest attacks.
Voters in Pattani, Yala and Narathiwat, who have been living under the yoke of military control even before the 2014 coup, rejected the draft Constitution in the referendum, he noted.
The attacks could be a way for the insurgents to demonstrate their support for local sentiments, he told The Sunday Times.
Yesterday, some blast sites were cleaned up and reopened to the public, while many shops and restaurants in Hua Hin - the upscale seaside district struck by multiple bombings that killed two people - reopened for business.
S'poreans going ahead with Thailand travel plans
Mr Julian Chia, 28, is heading to Bangkok at the end of this month. The tattoo artist and his girlfriend are among Singaporeans who have not cancelled or postponed trips to Thailand despite the string of bombings last week.
He said: "We have already booked the trip and it'll be quite wasteful to cancel. We'll try to stay safe, register with the Ministry of Foreign Affairs (MFA) and hope that nothing happens."
Popular tourist spots in Thailand, such as the seaside resort town of Hua Hin and Phuket island, were among those hit by explosions on Thursday night and Friday morning.
Four Thai people were killed and more than 30 others, including foreigners, wounded.
No one has claimed responsibility for what is being seen as coordinated attacks, but police have ruled out international terrorism.
"Luckily, the long weekend is over, so most of our customers are back in Singapore," said Ms Alicia Seah, Dynasty Travel's director of marketing communications.
Her agency now has fewer than 10 Singaporeans in Phuket, Chiangmai and Bangkok, compared with 130 over the National Day weekend.
The 200 Singaporeans booked with Dynasty Travel for trips to Thailand at the end of this month have also not called to postpone or cancel.
Thai Tourism Minister Kobkarn Wattanavrangkul remains confident that the attacks would not affect the tourism industry, which accounts for at least 10 per cent of the nation's economy.
"The confidence in tourism will return. Thailand solves problems very quickly and always bounces back," the French news agency, Agence France-Presse, quoted her as saying yesterday.
Last August's bombing at a Bangkok shrine - killing 20 people, mostly tourists - hardly made a dent on the industry as Thailand welcomed a record 30 million travellers in 2015.
Singapore's Ministry of Foreign Affairs said on Friday it had contacted most of the registered Singaporeans in the affected areas and verified that they are safe.
"Singaporeans in Thailand are advised to exercise vigilance and monitor the local news and instructions of the Thai authorities," said the ministry.
Some 20 foreign embassies in Bangkok have issued similar advisories to their citizens, The Nation daily reported.
Additional reporting by Koh Xing Hui
This article was first published on August 14, 2016.
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