One person was killed while three others were severely injured in an explosion at a fireworks factory in Thailand.

Terrified workers fled as the blast ripped through the farmhouse-turned-factory in Suphanburi province on November 30 morning.

The accident left the building in ruins, with one person, identified as Bualoy Boonprasert, 53, found dead in the wreckage.

Three more people were rescued and rushed to the Chao Phraya Yommarat Hospital after suffering severe burns on more than 50 per cent of their bodies.

Officers named them as Thara Watcharapimonmit, 28, Thongchai Kamnodnon, 55, and Sommai Thongchuea, 51.

Local media reported that the explosion began from a smouldering pile of coals believed to have ignited the factory's stock of gunpowder.

Suphanburi governor Natthapat Suwanprateep had arrived to inspect the scene.

He said the explosion occurred due to negligence as the burning coals were not properly extinguished. Locals are still barred from entering the area which has not yet been cleared for safety.

Police are continuing investigations.