A huge explosion has rocked a shopping centre in Thailand's capital Bangkok. State television said the blast took place in Ratchaprasong, at a road junction near the Erawan Shrine, and reported five people were dead, while 20 were injured.

BBC journalist Jonathan Head said he saw at least 12 bodies. He saw a massive crater that indicates it could be a bomb. Reuters and AFP quoted Thai police as confirming a bomb explosion took place in the busy road junction.

"I can confirm it was a bomb, we can't tell which kind yet, we are checking," national police spokesman Lietenant General Prawut Thavornsiri told AFP.

A Bangkok-based producer tweeted photos of the "very bad" scene:

The Buddhist shrine popular with Chinese tourists is likely to have been busy at the time of the explosion.

An AP reporter said he saw one body and body parts, and two people taken into ambulances.

The Ratchaprasong intersection has been at the centre of many heated political demonstrations in recent years. In March 2006, a mentally unstable man was beaten to death by bystanders after he damaged the Erawan shrine with a hammer.

Police and ambulances rushed to the scene after the bomb went off around 19:00 local time (12:00 GMT). Local police said the bomb could have been hidden in a motorcycle.

A Thai blogger quoted a national police spokesman as saying that the source was IED (Improvised Explosive Device) and two more bomb were reported nearby. The shopping mall has been shut down.

A CCTV video posted on social media appears to show the moment of the blast.

It is still unclear who might be responsible for the blast. Thailand is battling an Islamist insurgency in the south, but attacks in Bangkok are extremely rare. The Bangkok Post reported that a foreign national, possibly a tourist, has been injured in the blast.

UPDATE: Local reports say a second bomb has been found in front of Gaysorn shopping centre at Ratchaprasong.