When serial bomb blasts wreaked havoc in Mumbai in 1993, RDX became a part of our daily lexicon. Media reports about the use of RDX, a military-grade high explosive, in any bomb-blast automatically implied that the blast was serious and involved 'a foreign hand'. While RDX still evokes those images, terrorists have since moved on to less scary but equally potent explosives. The foremost among them has been ammonium nitrate, a chemical legitimately used in the agricultural sector as a fertiliser. It can also be easily extracted from another commonly available fertiliser, calcium ammonium nitrate. Mixed with fuel oil, it creates a highly destructive explosive called Ammonium Nitrate Fuel Oil (ANFO).

While it was known as an explosive even earlier, the use of ANFO has been popularised by al Qaeda and its affiliates in Afghanistan. This has led to a complete ban on production, import and usage of ammonium nitrate in Afghanistan although it continues to be illegally smuggled in from Pakistan. In fact, US Defence Department believes that about 85 per cent of the Afghan IEDs are made with ammonium nitrate smuggled from Pakistan.

Fatal blow: After the Zaveri Bazaar blast in Mumbai the government
declared ammonium nitrate as an explosive substance

Despite US insistence, Pakistan has refused to ban the production of ammonium nitrate. Although the first known case of ammonium nitrate being used in India is believed to be in the Delhi bomb blasts of 1997, its more widespread use was reported only in 2006 -- explosions in Varanasi, Lucknow, Jaipur, Faizabad, Hyderabad, Bangalore and recently in Mumbai. Ammonium nitrate has suited terrorists well as it is more readily available and raises far less suspicion. It is both cheap and harder to track down than more destructive alternatives like the RDX. Moreover, it provides Pakistan with plausible deniability because a military-grade explosive can be easily traced to ordnance factories in that country.

Two separate acts govern the production, supply, sale, possession and usage of explosives in India. Explosive Substance Act of 1908, overseen by the Home Ministry, deals with exploding, making or possessing explosives under suspicious circumstances while the Explosive Act of 1884, under the Commerce Ministry, regulates the manufacture, sale, transport, import and export of explosives. The move to restrict the use of ammonium nitrate was initiated after the 26/11 terror attacks when in December 2008, the home ministry notified it as a 'special category explosive substance' under the 1908 Explosives Substances Act. This notification only provided preventive and punitive measures for possession and misuse of ammonium nitrate. The more crucial amendments -- in the 1884 Explosives Act -- for regulation of the substance were made in July this year, following the Zaveri Bazaar blasts, when the government declared 'ammonium nitrate or any combination containing more than 45 percent of ammonium nitrate' as an explosive substance.

The very comprehensive Draft Ammonium Nitrate Rules-2009 drawn up a few months after the 26/11 terror attacks were not notified as the government feared that genuine users could face stiff penal action. These rules included restricting the supply, transport and sale of ammonium nitrate by issue of permits. These  rules have again been trotted out last week after the Rajasthan High Court sought explanation from the Central government about imposing a blanket ban on sale of ammonium nitrate. But it is not ammonium nitrate alone that India has been lax about.

Some 20,000 kgs of slurry explosives was stolen in 2007, with little or no police action. Explosives and detonators issued for mining continue to be diverted to the Maoists. India has failed to regulate ammonium nitrate with laws which several countries like the USA, UK and Australia did years ago. Furthermore, it has poorly implemented the laws already in place. Although Indian government seems to be waking up from its long slumber on this key security issue, there is genuine fear that its actions are insufficient to prevent the misuse of ammonium nitrate by terrorists in the future.

Sushant K Singh is Fellow for National Security at the Takshashila Institution and editor of Pragati- The Indian National Interest Review.