Sunbury residents were allowed to return to their homes last night, almost 24 hours after being evacuated following a dangerous chemical explosion. Police special operations group, drug squad officers and forensic chemists yesterday stabilised hundreds of litres of volatile chemicals that are used in the manufacture of amphetamines. The chemicals, stored in large containers in a shed at a Sunbury (Australia)self-storage depot in Evans Street, caused an explosion and ammonia cloud on Wednesday afternoon.