Toxic Terrorism
The recent suspected terror plot of 26 June 2026 also could be viewed as an attempt to ensure mass casualties amongst the people participating in the Muharram procession. Apart from the intention of causing mass casualties, the other terror dimension of this plot needs critical analysis, and that is the use of a toxic substance. The terror tactic used in this case was to inflict large-scale casualties through the covert dissemination of toxic agents. It bears the charter of using biological or chemical substances to cause many deaths, generate widespread panic and create religious disharmony.
In the past, India has witnessed a few criminal cases involving the covert use of toxic substances as weapons. One such known example was the Visha Oosi (poison injection) murder case during the 1970s in Chennai. Between December 1970 and October 1972, seven people were allegedly murdered using poison-filled syringes by a criminal gang that included a drugstore owner. Decades later, in April 2015, another similar case happened when a Chennai-based businessman was involved in murdering three individuals by modifying an umbrella to conceal a syringe mechanism. The umbrella’s tip was removed and replaced with a syringe reportedly filled with a highly toxic substance, possibly potassium cyanide.[3]
These cases underscore how readily available chemical substances could be modified into a killer weapon. It is important to note that the plot unearthed in Mumbai is not about some personal dispute or revenge, but appears to be a case of terrorism that bears characteristics commonly associated with both mass casualty terrorism and chemical or biological terrorism.
The most well-known example of biological terrorism is about the involvement of a Rajneeshee cult group. In the US, during 1984 in The Dalles, Oregon, members of the Rajneeshee cult deliberately contaminated salad bars at local restaurants with a bacterium called Salmonella enterica serovar Typhimurium in an attempt to influence a county election by suppressing voter turnout.
The attack followed a political dispute over local governance, with the perpetrators seeking to incapacitate voters rather than kill them. The said contamination resulted in 751 reported cases of salmonellosis, including 45 hospitalizations. Epidemiological investigations traced the outbreak to salad bars at ten restaurants, where the bacteria were intentionally introduced into food. The incident demonstrated how readily available biological agents could be exploited for the purpose of creating terror.[4]
In India on 7 November 2025, security agencies had unearthed a plot to use ricin, a highly lethal toxin derived from castor beans. The idea was to launch an attack on crowded markets and government offices in various cities. The individual arrested in this case is known to have links with an Afghan national associated with ISKP (Islamic State Khorasan Province) and operatives in Pakistan.[5]
Against this backdrop, the incident of 26 June 2026 should be viewed not as an isolated criminal act, but as a potential case of mass casualty terrorism involving the use of poison as a weapon. It remains unclear whether the accused was acting alone (a lone wolf) or was part of a larger network. This act underscores the growing possibility that readily available toxic industrial chemicals and biological toxins could be exploited to inflict mass casualties or create panic in crowded public spaces.
Importantly, it needs to be realized how inexpensive, easily procurable substances can be weaponized against soft targets. There are various chemical substances and biological agents that are banned under the chemical and biological weapons treaty mechanisms (CWC and BWC). At present, there appears to be a tendency that people with a heinous mindset would try to weaponize the bio or chem agents, which are freely available in the market. All this highlights the need for stronger surveillance of hazardous chemicals, better intelligence-sharing structures, and enhanced preparedness among public health, law enforcement and forensic agencies.
It is important to realize that biological and chemical threats are no longer confined to state-sponsored (mostly covert) weapons programs or battlefield scenarios, where such agents could be used against soldiers. The convergence of terrorism, lone wolf radicalization, easy online access to hazardous materials, and increasingly available knowledge of toxic agents in open-source literature calls for stronger bio/chem security frameworks.
Beyond strengthening the CWC and BWC implementation measures, states like India should invest in integrated chemical-biological surveillance, rapid toxicological diagnostics, emergency medical response, and public awareness mechanisms. There is a need to invest in chem-bio sensors that can be deployed in crowded places to detect harmful chemical substances, pathogens, or biomolecules in the air.
The recent Mumbai toxic pills incident serves as a timely reminder that national security today extends far beyond conventional terrorism. Chemical and biological threats, even involving readily available toxic substances rather than any banned biological and chemical weapons, have the potential to cause mass casualties, spread panic amongst the masses, and disrupt national security on a significant scale.
[1] “‘Wanted To Kill 15,000’: Mumbai Man Caught With Toxic Pills At Muharram Event”, NDTV, 28 June 2026.
[2] “Press Release on the massacre of Sikhs in Chittsinghpora, Jammu & Kashmir on March 20, 2000”, The Embassy of India, Washington D.C., 27 May 2000.
[3] Vivek Narayanan, “The Toxic Trail of Syringe Murders in Chennai”, The Hindu, 1 May 2016.
[4] Robert Herriman, “Bioterrorism at the Salad Bar: 40 Years Ago in US History”, Outbreak News Today, 4 May 2024.
[5] Gangadhar Sai K, “Decoding the Foiled Ricin Plot”, Chemical and Biological Weapons Magazine, Vol. 20, No. 1, January–June 2026, pp. 11–16.
Group Captain (Dr) Ajey Lele (Retd.) is the Deputy Director General, MP-IDSA. This article was originally posted to the website of Manohar Parrikar Institute for Defense Studies and Analyses (MP-IDSA). Views expressed are of the author and do not necessarily reflect the views of the Manohar Parrikar IDSA or of the Government of India.
