Three children, who were lighting fireworks on the ground floor of a two-storey house in Howrah’s Uluberia, died after the room they were in caught fire on Friday evening.

A teenager who tried to douse the flames has been admitted to MR Bangur Hospital with burns, an officer in Howrah Rural Police District said.

A fire services department official said the children had gathered inside the house near Uluberia’s Gangarampur Bazaar to light fireworks in the evening. They slipped into the room apparently without the knowledge of their family members.

The firemen entered the room after putting out the flames and found the charred bodies of Ishan Dhara, 2, Momtahina Khatun, 5, and Taniya Mistri, 9, police said.

Manisha Khatun, 17, was admitted to hospital with burns.

The three children were taken to Sarat Chandra Chattopadhyay Medical College and Hospital, in Uluberia, where they were declared dead on arrival.

The room where they were lighting fireworks was used as a store for a grocery on the same floor.

“We suspect flames from fireworks landed on some flammable substance in the room. We found several burnt oil containers and boxes containing biscuits, pulses and other items. The mattress on a bed in the room was completely burnt,” the official said.

Abhoy Kumar Das, chairman of Uluberia Municipality, said residents of the locality tried to douse the flames by splashing water from buckets but they were unaware that some children were trapped inside.

Residents of the building, who ran to the first floor and the terrace after spotting the flames, were also unaware that a few kids were inside a room on the ground floor.

“At it was Diwali, two fire tenders were stationed on the main road, a stone’s throw from the building. The firemen reached the house within five minutes of seeing the flames,” Das said.

A fire services department official said they first found Manisha Khatun. She was taken to Sarat Chandra Chattopadhyay Medical College and Hospital, from where she was shifted to MR Bangur Hospital.

Fire and emergency services minister Sujit Bose said the department had started an investigation to know the cause of the fire and why it spread so fast. “The team that found the bodies of the children said they were all curled up in a corner of the room,” Bose said.

Swati Bhangalia, the superintendent of Howrah Rural Police district, said forensic samples will be collected to ascertain the cause of the fire.

“We have launched an investigation. The case is being probed from all angles,” said Bhangalia.

The firemen rescued two persons from a room on the second floor and an elderly woman from the roof.