A woman and two girls died when a retaining wall slipped on a building at Garodi-Naguri in Mangaluru on July 1.

Rescue workers, including SDRF and fire and emergency services department personnel, rescued a man and two girls who were also trapped under the debris. They have been hospitalised.

The retaining wall was beside a residential tile-roof building behind Kankanady police station. The wall collapsed amid heavy rains at about 4.55 a.m., Police Commissioner Sudheer Kumar Reddy said.

The building had four rented houses. Half of the roof of the building collapsed when the retaining wall slipped on the rear portion of the houses. Those who died and the ones who were rescued were from two different families.

Police gave the names of the deceased as Anamika Chourasia (8), Tanu alias Pari (4), both from Bihar, and Shantha (35) from Udupi.

Those who were rescued were identified as Alka (14), Anusha (11), both from Bihar, and Balakrishna (40) from Udupi.

Balakrishna’s family had been residing in the house for the past eight months. His wife Shantha, who died, worked in an ice cream factory at Adyar in Mangaluru.

A family from Bihar — Lalbabu (37), his wife Indu (34), and their children Alka (14), Anushka (11), Anamika (7), and Tanu (3) — had been residing in the house for the past eight years. Two of the children died, two others were rescued from under the debris while the parents could escape the crash even before SDRF and fire and emergency services personnel could reach the spot.

The Police Commissioner said that, prima facie, it appears that the retaining wall slipped onto the residential structure, causing the rear wall of the house to collapse.

“It is important to note that when a retaining wall is constructed after cutting into laterite or similar hilly terrain, the foundation of that wall must be keyed into stable rock strata, or reach a depth sufficient to ensure structural integrity. Also, provisions for drainage must be incorporated to prevent water ingress. Constructing a retaining wall at ground level without a stable base or adequate drainage leads to inevitable failure, often triggered by the buildup of hydrostatic pressure during the monsoon,” Mr. Reddy said.

“We (police) are investigating the structural integrity of the wall to determine the specific cause of failure. Directions have been given to register a case against those responsible for the substandard construction, and any unauthorised excavation that may have increased landslide susceptibility,” he said.

“The police will seek formal expert opinions as part of this investigation. Further legal action will be taken based on those technical findings,” Mr. Reddy said.

Minister in-charge of Dakshina Kannada district U. T. Khader, who visited the spot in the afternoon, condoled the deaths.

He instructed Deputy Commissioner H. V. Darshan to disburse compensation, ₹5 lakh each to the families of deceased. The expenses for treatment of the injured must be borne by the State government, Mr. Khader instructed. The Minister said ₹1.25 lakh will be released for the damaged houses.