Three workers of a salt industry died and seven others were injured after inhaling toxic gas inside a septic tank at Fatullah in Narayanganj Sadar upazila yesterday.

The dead are Shahabuddin, 38, and Almas, 28, of Patuakhali and Ibrahim, the details of whom could not be known immediately.

Witnesses and police said 10 workers went down to clean the septic tank of Molla Salt Industries at Dharmaganj around 2:00pm. They fell sick after breathing in poisonous gas there. 

Other workers rescued them from the tank and took them to Narayanganj 300-bed Hospital. On-duty doctors declared Shahabuddin and Almas dead.

Four critically injured were admitted to Dhaka Medical College Hospital. Of them, Ibrahim died there later.