The incident took place at a privately-owned factory which manufactured plastic beans near Vita roundabout in Korangi industrial area.
Six workers were cleaning the tank when they become unconscious after inhaling the hazardous chemical. They were shifted to Jinnah Hospital in critical condition, where five of them could not survive.
One of the workers is still in critical condition and is struggling for his life.
The dead were identified as Irfan, Mairaj, Abdur Rahim, Abdul Ghaffar and Arbaz. They were aged between 20-25 years and were residents of Korangi.
They had come to the factory to earn their bread and butter but the fateful incident occurred. The news of their tragic death has shocked their family members who are trying to recover it. They claimed that no safety precautions were provided to their loved ones.
Police have reached the place of the incident and have started investigations. A criminal case has been launched against the factory owner for negligence and lack of safety gear. Police have sealed the factory and arrested the watchman.