Bangkok was a city on edge last night (Tuesday night) after a second bomb blast rocked a riverside pier popular with tourists 24 hours after the bloodiest terrorist attack in its history.
Thai police released video footage that appeared to show the moment when a young man planted the bomb that ripped across the Erawan Shrine on Monday, a popular destination for locals and Asian visitors.
The official death count for the bombing reached 20, of whom 11 were tourists from East Asia, including Vivian Chan Wing-Yan, 19, a British-Hong Kong student. But some local media reports suggested the number of dead rose to 28 during the day, while the tally of injured passed 130, many of them badly wounded.
With no claims of responsibility and mystery still surrounding the bomber's motive, the Thai authorities appealed for help to find the suspect, who wore a distinctive yellow patterned T-shirt.
Yesterday another blast rang out across the city when an unidentified man threw the same sort of home-made pipe-bomb that caused Monday's carnage at a boat used by tourists and commuters.
The device narrowly missed a packed pier and exploded in the water, sending a huge plume of water across bystanders on the riverside.
The city braced itself for further attacks as the bomber who brought slaughter to the Erawan Shrine remained on the loose. Normally bustling streets, restaurant districts and shopping malls were near-deserted as residents and visitors followed advice to avoid areas that attract crowds.
"I thought it was a one-off when I heard the explosion on Monday night," said Sam Davies, a British tourist who had moved forward his plans to travel to the Thai islands.
"But I'm a bit freaked out after the second blast. I'm really not sure if someone is targeting tourists in Bangkok."
Prayut Chan-o-cha, the prime minister and head of Thailand's military junta, described the attack as the "worst incident that has ever happened" in the country.
One leading police official said the young man in the CCTV video was the presumed bomber.
The footage had unnerving echoes of the surveillance recordings that showed the Tsarnaev brothers as they planted the Boston marathon bombs in backpacks in 2013. The suspected Bangkok bomber even appeared to resemble the surviving brother Dzhokhar with his mop of unruly hair and wiry frame.
The video showed him sitting down calmly, a bulky black rucksack on his back, next to the railings at the spot where the huge explosion ripped across the temple 15 minutes later.
After walking through the crowds milling around the Erawan Shrine at one of the city's busiest intersections, he eased the bag off his back and left it behind as he stood up and appeared to look at his mobile phone or take a photograph.
Near him, others were unsuspectingly taking pictures of the Hindu deity that is renowned for bringing good fortune. Different cameras tracked the suspect as he headed away from the scene down the busy streets, all the time clutching a plastic bag as he walked, glancing frequently at his phone. One CCTV clock showed the time at 6.40pm, about 15 minutes before the blast.
The suspect then walked out of sight of the cameras, taking a motorcycle to leave the scene. Police believe that he left behind a pipe filled with explosives and wrapped in cloth. The result was one of unimaginable horror, said Marko Cunningham, a paramedic from New Zealand who has worked in Thailand for 15 years and responded to the emergency call.
"I have never seen injuries like it," he told The Daily Telegraph. "These poor people had been shredded. There were so many holes in them that I didn't know where to start trying to patch them up. The survivors were in a state of complete shock.
"We had to pull out the bodies of the dead to reach those who were still alive. Their friends and loves ones had taken the full impact of the blast and that is what saved them."
Mr Cunningham said that the most traumatic moment for him was prising the grasp of an injured young man from the fingers of his dead female companion.
"You could tell that he knew she'd gone, but he just didn't want to let go," said Mr Cunningham.
"Whoever did this really wanted to kill and maim. I cannot imagine how full of warped twisted hatred they must have been."