Never, never use a torch to dismantle old bombs for scrap.
http://www.theguardian.com/world/2014/apr/02/second-world-war-bomb-explodes-bangkok
Workers at a scrapyard in Thailand's capital accidentally detonated a large bomb believed to have been dropped during the second world war, killing at least seven people and injuring 19 others, police said.
Police bomb squad chief Kamthorn Auicharoen said construction workers found the bomb buried at a building site and sold it to the scrapyard in northern Bangkok. He said workers were using a gas-powered thermal cutter to take the bomb apart when it exploded.
The massive blast ripped apart the scrapyard in Bangkok's Lad Prao district and damaged nearby houses.
http://www.theguardian.com/world/2014/apr/02/second-world-war-bomb-explodes-bangkok