The accident occurred when a sweeper during a cleaning work fell into the tank and while trying to rescue him five others, including the owner of the factory, also fell into it and died due to the deadly chemical fumes, police said.
According to police, the pickle factory was operating illegally in a residential area in Korangi.
Industrial tragedies occur frequently in parts of Pakistan as laws regulating these factories are virtually never enforced by authorities and many of these small factories operate in residential area instead of industrial areas.