Two children injured in a CNG cylinder explosion at a godown in Sunder Nagri, north-east Delhi, succumbed on Sunday, a police officer said.

The deceased have been identified as Sakib, 7, and Raja, 4, both sons of Afsar. They had suffered over 85% of burn injuries in the blast and were undergoing treatment at the Guru Teg Bahadur Hospital.

Four persons, including the deceased, were seriously injured after a CNG cylinder exploded around 4:30 p.m. on Saturday at a storage-repair unit on the ground floor of a four-storey residential building.

According to the initial investigation, the blast was triggered during a repair operation. It was so powerful that it shattered the iron gate of the godown, with debris hitting the children who were playing nearby. Though no fire followed, the shockwave caused significant damage to the godown and nearby properties.

Given the deaths, the officer said Section 106(1) (death by negligence) of the Bharatiya Nyaya Sanhita (BNS) has been added to the case registered at Nand Nagri police station. Earlier, an FIR under Section 287 (negligent conduct with respect to machinery), 125A (endangering life or personal safety of others), and 326G (causing grievous hurt by use of explosive substance) of the BNS had been lodged.

CNG cylinders were being stored and repaired at the facility, which was operating without proper authorisation, the officer said, adding that legal action has been initiated against the owner of the godown, who was yet to be arrested.