Patna, Sep 10 (IANS): Four labourers died on Tuesday after they were exposed to poisonous gas inside a septic tank in Bihar's Muzaffarpur district, officials said.

District official Kundan Kumar said that the labourers died due to suffocation after they entered the septic tank to remove some construction material. "Prima facie, it is suspected that they died of suffocation inside the septic tank".

The labourers, who belonged to the same family, were trying to clean the newly-built septic tank in an under construction building in the Madhuban Kanti village.

Kumar said the district administration will provide compensation to the victims' family under the disaster management fund.

According to the police officials, the labourers were later pulled out of the septic tank and taken to a local hospital where they were declared dead. All of them were from one family and lived in the same village.

A case has been registered in connection with the incident.