A total of 23 persons were found stuck in the building many of whom were tenants. Some of them jumped to balconies of neighbouring buildings. Eight persons who sustained burn injuries were taken to two hospitals, Bhagat Chandra and DDU.
The accused Anil Kumar has been arrested, police said.
Kumar was held after the police scanned the CCTV cameras installed in the vicinity of the house. He was seen setting vehicles parked on the ground floor of the house on fire in the camera footage.
Those killed have been identified as Mamta's 65-year-old mother Kailash Rana, Jagdeep (32) and his one-year-old boy Akshay.
Jagdeep lived with his wife and son on the second floor and worked as a medical representative. Mamata was also injured in the fire.
The three-storeyed building has a basement which served as a parking lot. The building had six flats most of which were occupied by tenants.
Eight persons, including a fire officer were injured in the incident. Many of them who escaped the fire suffered fractures as they jumped off from balconies in a desperate bid to survive.
Crime team and a team of CFSL experts were called on the spot," said Deputy Commissioner of Police (South West) Suman Goyal.
