Four labourers from Assam died on September 27 after inhaling poisonous gas inside a septic tank in Meghalaya, officials said.

The victims were identified as Mofidur Rohman, 34, Ajiyer Rahman, 41, Ismail Hussain, 20, and Rakib Hussain, 22. They had entered the tank for cleaning work when they were overcome by suspected hydrogen sulphide and methane.

Two fire and emergency services personnel who went in to rescue them also fell unconscious and were hospitalised. They are reported to be in stable condition.

Septic tanks can accumulate toxic gases as organic waste breaks down without oxygen. Experts say such deaths remain common in India, where manual cleaning often happens without safety gear or breathing apparatus.

The Meghalaya government has ordered an inquiry into the incident. Officials said compensation for the families of the deceased would be considered.

All four workers were migrants from Assam’s Barpeta region. Their bodies were handed over to their families after post-mortem examination.