Thousands were evacuated in California as a leaking tank of toxic chemicals threatened a catastrophic explosion. The tank contains methyl methacrylate, a volatile substance, and fumes have spread over populated areas.

Firefighters warned on Saturday that a tank of toxic chemicals in California is heating up, adding to fears of a catastrophic explosion that has already forced tens of thousands of Californians to evacuate. About 40,000 residents were ordered to leave their homes in the Garden Grove area of Orange county, southeast of Los Angeles, on Friday after the tank began to leak, sending fumes over a heavily populated area. The tank contains 26,000 litres (7,000 gallons) of methyl methacrylate, a volatile...