At least 12 people have been killed and 78 wounded by a bomb blast that hit the commercial centre of the Thai capital Bangkok, police have said.

The blast, which was said to have taken place near the Erawan Shrine, occurred about 7.10pm local time, according to the Bangkok Post.

Nearby offices have reportedly been evacuated, according to reports on social media.

The bomb was placed inside the Erawan Shrine area, Defence Minister Prawit Wongsuwon said.

Thai Police said a second bomb is being defused inside the shrine.

Eric Seldin, of Thaicom Production Services, was 100 metres away when the explosion happened.

“I was inside the Hyatt hotel having dinner when we heard an extremely loud explosion near the Ratchaprasong intersection,” he told Al Jazeera. “The windows were shattered and everyone at the hotel was startled.

“Security tried to shut down the hotel and attempted to keep everyone inside but I was able to go out and walk just about 50 metres close to the intersection.

“I noticed seven to eight covered bodies. There was damage to the ground of the shrine.

“On the street itself there were several casualties. There is a large security presence. Police are moving people back because they are worried about the second explosion.

“The area is extremely close to the National Police Headquarters and the police hospital,” Seldin said.

The bomb squad is also on the scene of the blast, possibly looking for any other devices. There has been no claim of responsibility.

Thai forces are fighting a low-level Muslim insurgency in the predominantly Buddhist country’s south, although those rebels have rarely launched attacks outside their ethnic Malay heartland.

The country has also been riven for a decade by intense and sometimes violent rivalry between political factions in Bangkok and elsewhere. Al Jazeera