Thai authorities on Saturday hunted for culprits behind a wave of bombings targeting the country's key tourism sector, as businesses in top destinations braced for the full impact.
The kingdom was on edge after 11 small bombs exploded across five southern provinces on Thursday night and Friday morning, killing four locals and wounding more than 30 people — including foreign tourists.
The bombs, most of them detonated in twin blasts, struck key tourism hubs during a long weekend, including the seaside resort town of Hua Hin and the island of Phuket.
No one has claimed responsibility for the attacks, but police have ruled out international terrorism and said the campaign was an act of "local sabotage".
"There have been no arrests yet," deputy national police spokesman Piyapan Pingmuang told AFP Saturday morning, adding that police have yet to identify any suspects or a motive.
Authorities have also been quick to downplay possible links to a simmering Islamic insurgency in Thailand's southern border region.
If the Muslim rebels are to blame, it would mark a major expansion of a secessionist campaign that has been concentrated further south and rarely targets foreigners.
Analysts said it would also be a huge embarrassment to Thailand's coup-installed military government, which has made boosting national security a flagship policy of its regime.
In hardest-hit Hua Hin, a popular beach resort rocked by four bombs in 24 hours, locals braced for a blow to the town's mainstay industry ahead of peak tourist season.
"Hua Hin has never had a problem like this," Nai Amporn, the owner of a beachside restaurant, told AFP.
"I am afraid business will become slow — even this morning, you can see there are less people here for breakfast. I think they have all gone home," he added.
Record year for tourism
Hua Hin, about 200 kilometres (125 miles) south of Bangkok, is a popular stop for local and foreign travellers. It was for years the favourite seaside retreat of King Bhumibol Adulyadej, the world's longest reigning monarch.
The 88-year-old is currently hospitalised in Bangkok, a source of anxiety for many Thais and a key factor in the kingdom's past decade of political turmoil.
The blasts erupted on the eve of Queen Sirikit's 84th birthday, also celebrated as Mother's Day in Thailand.
Famed for its idyllic islands and Buddhist temples, Thailand is a tourism powerhouse and was hoping for a record 32 million visitors in 2016.
The industry accounts for at least 10 percent of a lagging economy that the military government, which came to power in 2014, has struggled to invigorate.
Anthony Davis, a security analyst at IHS Jane's, said the bombings were aimed at the heart of the tourism sector.
"My assessment is that this whole operation was targeted on one thing: Thailand's tourist economy. This will have a significant impact on the tourist season in the south this year and into early 2017," he told AFP.
Thailand's reputation as a holidaymaker's paradise has in recent years weathered bus and boat accidents, bouts of political unrest and high-profile crimes against foreigners.
After the latest bombings, two Swiss travel companies, Hotelplan Suisse and Kuoni Suisse, said clients with trips to Thailand before 15 August could change or cancel their plans for free, according to Swiss public broadcaster RTS.
In the past, the industry has shown a knack for rebounding quickly.
An August 2015 bombing at a Bangkok shrine that killed 20 people — mostly tourists — was followed by a sudden drop in visitors but did not stop the kingdom from welcoming a record high of nearly 30 million travellers that year.