At least seven people were killed and 19 others were injured when a suspected World War II bomb exploded at a scrap metal warehouse in Bangkok as workers tried to cut it open.
The shell was found at a construction site by builders who then sold it to a suburban scrap metal merchant believing the bomb had been defused.
"The workers at the warehouse thought the bomb was no longer active so they used a metal cutter to cut into it causing the explosion," said local police commander Virasak Foythong, adding the ordnance was probably left over from the war era.
Television footage showed debris and twisted metal at the destroyed workshop as thick smoke choked the sky, while local reports said dozens of nearby homes were also damaged by the blast.
The allies conducted bombing raids on the Thai capital in retaliation for the kingdom joining the Japanese war effort in Southeast Asia.