Bangkok, April 3 (RHC) -- A bomb believed to be from the World War II period exploded in the Thai capital Bangkok on Wednesday, leaving at least seven people dead and 19 others injured.

The 225-kilogram bomb exploded when a worker at a scrap metal warehouse in the Bang Khen district, who reportedly did not realize it was a bomb, tried to cut it open.

The bomb was probably left over from the World War II era, local police commander, Virasak Foythong, was quoted by the Nation newspaper as saying.

Five people died on the spot. The blast also caused a big fire and damaged dozens of nearby houses.

The bomb was initially discovered by a worker at a construction site near the warehouse, who reportedly did not know it was a bomb and sold it to a scrap metal merchant.