Children of ITL Public School in Delhi on Wednesday quickly went under the desk when they heard the sound of a siren.

Principal Sudha Acharya addressed them, stressing the importance of being prepared.

On the day the Indian military launched Operation Sindoor targeting terror infrastructure in Pakistan and Pakistan-occupied Kashmir (PoK) in a strong response to the Pahalgam attack, a civil defence mock drill named Operation Abhyaas was carried out in 244 civil defence districts across the country.

The event was a learning experience for the citizens on how to save themselves from any possible attack or situation at the time of a conflict. This was the first time since the 1971 India-Pakistan war that such a drill was carried out.

“We highlighted the need for emergency kits, identifying safe zones like basements or shelters, and keeping essential supplies like food, water and medicines ready,” Acharya said.

The ministry of home affairs had issued a protocol for the drill that involved mass evacuation, bunker safety, blackout protocols and training of civilians in basic survival tactics in crisis situations.

The primary objective of the mock drill included assessment of the effectiveness of the air raid warning system, operationalisation of hotline/ radio communication link with the Indian Air Force, provision for early camouflaging of vital installations, and verification of activation and response of civil defence services.

In the evening, several areas in Delhi witnessed blackouts. Residents were seen using candles. They preferred to stay indoors.

At Khan Market in New Delhi, National Disaster Response Force (NDRF) personnel demonstrated techniques of safety and rescue operations during the drill. Civilians were seen watching them to understand the safety protocols. Civil defence officials, Delhi police and fire department personnel also coordinated with the NDRF in the drill.

Blaring sirens, residents rushing to safer places, and injured people being carried away on stretchers — these were some of the scenes that played out across the 55 locations where mock drills were carried out by the authorities in Delhi.

In Mumbai, mock drills were conducted at strategic locations, including the railway stations.

A civil defence team from Central Railway organised a mock drill at Mumbai’s Chhatrapati Shivaji Maharaj Terminus, one of the busiest stations and a site of the 26/11 terrorist attack, to test the preparedness of security forces in case of an emergency.

As part of the exercise, RPF and the GRP personnel conducted separate and joint security drills.

Security has been heightened at all railway stations and in several areas across the city. Mumbai police personnel were seen on patrol, officials said.

In Bengaluru too, a large-scale civil defence mock drill was conducted at various locations.