Red Fort blast: Agencies focus on use of fuel, detonators, ammonium nitrate

According to a source, forensic experts and Delhi Police suspect that the car was carrying approximately 60–70 kg of ammonium nitrate—an odourless white crystaline chemical—and the explosion was triggered by a detonator or timer.

“At this point, we cannot ascertain what kind of components were used to carry out the blast. Some possible evidences were completely washed away with the water that was used for dousing the flames. However, multiple exhibits collected from the site will help determine the type of composition involved,” an officer said.

The Delhi Police have registered a case under sections 16, 18 of the Unlawful Activities (Prevention) Act (UAPA) and Explosives Act at Kotwali Police Station in North Delhi.

Sources in the security establishment told The Indian Express that concrete evidence of an IED being there in the car is yet to be found. “No wires, timer devices, detonator, batteries or even shrapnel have been found at the spot. However, a second and third inspection is still being done to even scan the area beyond the blast site. But as yet, we have no evidence to confirm or deny an IED,” a senior official aware of investigation details said.

“As yet, we have only found traces of ammonium nitrate from the spot. As of now it looks unlikely if there was any other explosive, but investigation is on,” said another official.

Sources, however, said the forensic tests, the severity of the blasts and the circumstances of the chain of events do push the investigations towards a terror conspiracy. “It appears the explosive may have been part of the Faridabad haul of 350 kg of ammonium nitrate confiscated on Sunday. The links are being further explored, some suspects are being questioned by the J&K police in this regard,” the official said.

“There are many kinds of IEDs, not all require timer devices. Some are pressure induced, some can be triggered with heat, even with acid. We are still at preliminary stage of the probe, nothing can be said with certainty,” an official said.

The investigators are now focussing the links of the suspected car driver, Umar Nabi from Pulwama.

Meanwhile, the MHA Tuesday also handed over the probe to the NIA.