Four persons were suffocated to death in Jharkhand's Garhwa district on Friday while they were attempting to clean a septic tank, police said.

Three of the deceased are brothers, they said.

The incident happened in Nawada village, DIG (Palamu Range) Naushad Alam told PTI.

The victims were identified as Ajay Chaudhary (50), Chandrashekhar Chaudhary (42), and Raju Shekhar Chaudhary (55), the brothers, and Maltu Ram, police said.

The men suffocated after being exposed to toxic gases as they opened the lid of the septic tank.

An investigation is underway, police said, adding that the bodies were sent for post-mortem examination.

SDPO Neeraj Kumar said, "Three of the victims were real brothers who were working on the construction of their septic tank. During this time, a laborer went down into the tank but did not come back out. One by one, all three brothers went in after him, but none of them returned. It was later discovered that when they were finally pulled out, they had already died inside."

Deputy Superintendent, Sadar Hospital Mehroon Yamini said, "All four were brought in dead. The information we received is that they had gone into the tank and were unable to come out. Their bodies were later retrieved and brought here."

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