A large explosion has rocked a central Bangkok intersection during the evening rush hour, killing several and injuring an unknown number of others. Police officers at the scene have also detonated a second bomb, according to reports.
The cause of Monday's explosion, which sounded like a loud thunderclap to people living nearby, was not immediately known.
Local media is now reporting that at least 16 people have been killed and 80 have been injured. The dead included Chinese and a Filipino, national police chief Somyot Poompummuang said.
"Those who have planted this bomb are cruel. They aim to kill because everyone knows that at 7 p.m. the shrine is crowded with Thais and foreigners. Planting a bomb there means they want to see a lot of dead people," he said.
The country's national chief said the blast was caused by a bomb. Police said the bomb was on a motorcycle when it exploded outside a Hindu shrine in the centre of the Thai capital.
"All I can say now is there has been an explosion in central Bangkok involving a motorcycle bomb," deputy national police chief Aek Angsananond told Reuters.
No group has yet claimed responsibility for the attack but government figures believe it was aimed at the economy.
"We still don't know for sure who did this and why," Deputy Prime Minister Prawit Wongsuwon told reporters. "We are not sure if it is politically motivated, but they aim to harm our economy and we will hunt them down."
The aftermath of the blast in the Thai capital.
The explosion took place at the Rajprasong intersection, which was the center of many contentious political demonstrations in recent years. It appeared to have occurred in front of the Erawan Shrine, a tourist landmark also popular with Thais.
Shocking video footage appears to have emerged on social media in the wake of the incident, highlighting the scale of the blast.
Video via Voice of America/Periscope/Steve Herman
BBC reporter James Sales was nearby when the explosion happened. He described the moment he tried to save the life of one victim: "The windows didn't shatter but we knew it was a big bomb nearby... I saw at least nine people who looked like they had died. I tried to do CPR on one man in his 40s but he didn't make it. There were people with such horrific injuries."
Thailand's capital has been relatively peaceful since a military coup ousted a civilian government in May last year after several months of sometime violent political protests against the previous government. However, there has been some tension in recent months as the ruling junta has made clear it may not hold elections until 2017 and wants a constitution that will allow some type of emergency rule to take the place of an elected government.
Car bombs are almost unknown in Bangkok, but have been used in southern Thailand, where a Muslim separatist insurgency has been flaring for several years.
The last major bombings in Bangkok occurred on New Year's Eve at the end of 2006, when a series of bombs at celebrations around town killed at least three people and wounded dozens. Those bombings occurred just three months after a military coup ousted Prime Minister Thaksin Shinawatra, and there was speculation that his supporters carried out the attacks in revenge. However, the bombings were never solved.
The 2006 coup set off a battle for power among Thaksin's supporters and opponents, sometimes in the form of violent protests.
Protesters from both sides sometimes faced armed attacks by unknown groups, with more than 90 people killed in 2010 during pro-Thaksin demonstrations that were quashed by the army. The focus of the 2010 protests was the same intersection where Monday's blast took place, a bustling area in the heart of Bangkok's main shopping district. Several five-star hotels are nearby.
In March this year, several arrests were made in connection with a grenade that was tossed at Bangkok's Criminal Court. Those detained were apparently sympathizers of the pro-Thaksin Red Shirt movement. Critics of the current military government say some of the bombings may have been carried out by the junta to justify its continued suppression of basic rights and liberties. The government denied that.
In April, a car bomb exploded at a shopping mall on the resort island of Samui, injuring seven people. The motive was unclear, though the government suggested it was linked to politics.
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The Associated Press contributed to this report