Three people — including two children — died on Sunday, likely due to toxic gases and lack of oxygen, after being stuck inside a 100-foot-deep well at a residential building near Fawara Chowk in Garden, police said.

While talking to Dawn.com, Deputy Inspector General of South-Zone (DIG-South) Syed Asad Raza said the children fell into the well while playing near it.

The DIG said the well’s cover was broken while the children were playing near at, and they “most probably” died after inhaling toxic gases.

He said that another probable reason for the death of the children could be the lack of oxygen inside the well.

In an attempt to rescue the children, a passerby descended into the well, but he also died, the police official said.

The DIG South revealed that Sunny Builders had dug up a 100-feet-deep well in their housing project, adding that the South police chief had directed Garden police to initiate criminal proceedings against the owners and builders of the residential building.

Meanwhile, Sindh Government’s Rescue-1122 official Hassaan Khan said that he received information of two children — identified as Badar Sohaib, 8, and Talha Asif, 10 — falling inside the well at the residential apartment in Garden East.

A rescue team rushed to the spot upon receiving information, he said.

“The rescue operation continued for five hours,” Khan said, adding that they faced difficulties because of the presence of toxic gases inside the well.

The rescue service’s official said that all three bodies were recovered.

He said that the passerby who attempted to help the children was pulled out from the well in an unconscious state, but was pronounced dead at Dr Ruth Pfau Civil Hospital Karachi.

Police surgeon Dr Summaiya Syed confirmed that three bodies were received by the Civil Hospital Karachi (CHK) to fulfil their legal formalities.

The police surgeon said the exact cause of death would be ascertained after a post-mortem examination.