The National Security Guard has informed the Delhi police that the IED recovered recently from the Ghazipur flower market had a timer device attached to it and had ammonium nitrate and RDX as its components, official sources said on Monday.
The federal counter-terrorist commando force had sent experts from its National Bomb Data Centre based in Haryana's Manesar to defuse the improvised explosive device that was recovered in New Delhi on January 14.
The sources said a final post-blast investigation report has been submitted to the Delhi police and it states that the IED contained ammonium nitrate, RDX, a 9-volt battery, iron pieces that could act as shrapnel during an explosion and had a timer device attached to it.
The RDX was used as the core explosive in the IED but it did not blow off due to a "glitch" in the circuit, they said quoting the investigation report.
The force had defused the about 3-kg IED that was kept inside an iron box and concealed in a black backpack.
A pit was dug at the "phool mandi" or the flower market campus and the IED was blown under a "controlled explosion" procedure by the NSG personnel.
The incident has been taken very seriously by the Delhi police and other security agencies as it came just days before the January 26 Republic Day celebrations, for which the security apparatus in the national capital is on a high alert.