NEW DELHI: Two days after a fire tore through a five-storey residential building in southeast Delhi’s Tughlakabad Extension, killing three people and injuring eight others, police said that the blaze was a deliberate act of arson and have nabbed four persons, including a 17-year-old girl.The fire broke out around 2.24am on June 12 at a Building in street No. 1. The flames quickly spread from the ground floor to the fifth floor, engulfing the building and trapping several residents inside.Eight people suffered burn injuries and were rushed to AIIMS Trauma Centre and Safdarjung Hospital. Three victims — Pankaj Pandey, Sonia Kumari and Sushila Devi — later succumbed to their injuries.Read more: Mumtaz saved 2 sisters, but futile search for cat landed her in ICUPolice had initially registered a case under provisions relating to negligent handling of fire and causing death by negligence. However, as reported earlier, during the investigation, CCTV footage showed a woman entering the premises shortly before the blaze broke out, prompting investigators to probe the possibility of foul play.The investigation led to the apprehension of a 17-year-old girl who allegedly told cops that she had been told to set fire to a scooter belonging to Deepak, a resident of the building’s fifth floor. “The teenager said that she had been instructed by a 27-year-old woman, who provided her with petrol and a matchbox and directed her to target the vehicle over a monetary dispute involving Deepak,” a senior police officer said. TOI was the first to speak to Deepak, a bike taxi driver, on the day of the fire at the Safdurjang hospital’s burn ward as his wife, Mumtaz was in ICU critical, and his two sisters in law were also critical at AIIMS burn ward. Police said the 27-year-old woman, in turn, revealed during questioning that she had acted at the behest of a 33-year-old man and his 27-year-old brother. Investigators suspect the fire was part of a conspiracy hatched to settle a personal dispute.Following the findings, police added sections related to criminal conspiracy, culpable homicide, attempt to commit culpable homicide, mischief by fire and house trespass by night. All four suspects have been apprehended, and further investigation is underway.Investigators are now examining the exact chain of events that led to the fire and how a plan allegedly aimed at damaging a parked scooter escalated into a blaze that claimed three lives and left multiple others critically injured.