Hajipur, March 1 -- Four members of a family, including a father-son duo, died of asphyxiation after entering a septic tank in Vaishali district of Bihar on Sunday, administrative and police officials said.

Sadar Sub-Divisional Magistrate Rambabu Baitha and Lalganj Sub-Divisional Police Officer Gopal Mandal said here that one person reportedly entered the soak pit of a toilet tank in Anwarpur village under Sarai police station's jurisdiction and fell unconscious due to toxic gases inside.

In an attempt to rescue him, other family members went in one after another. However, they too came under the impact of poisonous fumes and suffocated to death.

Three other persons were seriously injured in the incident and have been admitted to a nearb...