The Crime Branch of Delhi Police on Monday ran a 3D laser scan on the building in Anaj Mandi near Filmistan that engulfed in a blaze on Sunday killing 43 people, to recreate the how the situation unfolded.
A team from the Forensic Science Laboratory (FSL) also visited the site and collected samples from the four-storey building that housed a number of illegal manufacturing units and had stored flammable raw material such as cardboard boxes, plastic sheets and rexine.
This is the second time that the Delhi Police is using the 3D laser scan technology for investigation.
The police had used the same technology to probe the massive fire in February in Karol Bagh's Hotel Arpit Palace that killed 17 people.
A Delhi court on Monday sent to 14-days police custody the property owner, Rehan, and manager of the building, Furkan.
Metropolitan Magistrate Manoj Kumar accepted the police's plea seeking their custodial interrogation.
Police had arrested the two and registered a case under sections 304 (culpable homicide not amounting to murder) and 285 (negligent conduct with respect to fire) of the IPC. The case was transferred to the Crime Branch.
The Delhi government had ordered a magisterial probe into the tragedy, the worst fire accident in the national capital since the 1997 Uphaar cinema blaze that claimed 59 lives, and sought a report within seven days.
It took over 150 firefighters nearly five hours to douse the blaze. As many as 63 people were pulled out of the building. While 43, including one minor, died, 16 were injured. Two fire department personnel were hurt while carrying out rescue work, officials said.
Almost all the deceased were migrant labourers hailing from Bihar and Uttar Pradesh. Police and fire department officials said many of the fatalities occurred due to suffocation as the people were sleeping when the fire started at around 5 am on Sunday on the second floor of the building that did not have fire safety clearance.