Ammonium Nitrate Found In Red Fort Blast, Say Investigators
Nine people died near Delhi’s Red Fort; police suspect ammonium nitrate was used in the blast.
The tragic explosion near the Red Fort Metro Station on November 10, 2025, which claimed nine lives and injured more than 20, involved ANFO (Ammonium Nitrate Fuel Oil), a widely available industrial explosive packed into a Hyundai i20 car and likely triggered manually, authorities confirmed on November 11. Forensic analysis by the National Investigation Agency revealed residues of ANFO—a mixture of ammonium nitrate prills and fuel oil in a 94:6 ratio—indicating a suicide-style attack in the crowded Old Delhi area. This low-cost, high-volume compound, commonly used in mining, requires a booster like a detonator for initiation and produces a broad shockwave rather than focused fragmentation. The incident, hours after a 2,900 kg explosives seizure in nearby Faridabad, has heightened national security, with the Red Fort closed until November 13 for probe access.
ANFO stands apart from RDX (Research Department Explosive, or cyclotrimethylenetrinitramine), a pure synthetic high explosive developed in the 1920s and pivotal in World War II for Allied and Axis munitions due to its compact power. While ANFO is a binary blend—oxidizer-rich ammonium nitrate sensitized by diesel—RDX is a single nitroamine molecule with three nitro groups on a triazine ring, enabling self-sustained detonation without additives. ANFO's detonation velocity ranges from 3,200 to 4,500 m/s with an energy output of about 3,700 kJ/kg, making it suitable for large-scale blasts but less brisant (shattering) than RDX's 8,750 m/s speed and 5,000 kJ/kg yield. In the Red Fort case, ANFO's volume amplified damage through fire and debris in a confined vehicle, unlike RDX's precision for armor-piercing shells.
Key differences lie in composition, production, and application: ANFO is cheaply mixed on-site from fertilizer-grade ammonium nitrate (India produces 2.5 million tons yearly), costing under $1 per kg and stable until boosted, ideal for improvised threats like the 1995 Oklahoma City bombing. RDX demands lab synthesis via nitrolysis of hexamine with nitric acid and ammonium nitrate, peaking U.S. output in the 1960s at third globally by volume, and forms bases for plastic explosives like C-4. ANFO generates lower pressure (70,000 atm) for earth-moving, while RDX's 300,000 atm excels in military contexts, often blended with TNT for amatol variants during wartime scarcity.
The blast's use of ANFO highlights regulatory gaps in fertilizer oversight, echoing the 2019 Pulwama attack, as probes under the Explosives Act trace sourcing to a suspected Jaish-e-Mohammed module. Unlike RDX's controlled military chains, ANFO's accessibility poses urban risks, prompting calls for enhanced tracking to prevent low-tech escalations in India's megacities.
