"There are three kinds of lies: lies, damned lies, and statistics."
A recent article published on Scroll India revisits the question whether “Most terrorists in India are Muslims”. 
The debate is disingenuous to begin with, in addition to my personal aversion to the question; there is no credible data on religious composition of the cadre of various terrorist outfits. Any approximation on the basis of religious affiliation of terrorists in captivity would most likely be subject to a bias (Over 28% of those incarcerated in India in 2012 were Muslims, much higher than their population share).
Mr. Patel instead cites terrorist fatalities data, collated by South Asia Terrorism Portal (SATP), as evidence of most terrorists in India being Hindus. Referring to fatalities’ statistics between 2011 and 14, the writer concludes that “As is obvious, most terrorists in India are Hindus, the ones whom we have conveniently labelled 'Maoist' instead of 'Hindu'. The second largest group of terrorists is the tribals, animists and perhaps some Christians, of the Northeast. Muslims are third.”
The writer could have framed the question better as “Is X religious group responsible for most terrorism related violence in India?” given the paucity of data to tackle the original hypothesis.
More importantly, the author makes a not so obvious assumption that all Maoists are Hindus. Since Maoism or Naxalism is a class based struggle- it is difficult to pinpoint the religious affiliation or belief of their cadres. While the writer is happy to ascribe Maoism as a smokescreen for Hindu terror, it would have been instructive to see what Naxalite groups have to say about Hindu or Hindutva beliefs. The Communist Party of India (Marxist Leninist) declares itself as “the highest political organisation of the Indian proletariat fighting for realising its supreme class mission”, without a reference to any religious affiliation.
The point being that Naxalite groups, unlike Islamic or Hindutva terror outfits, should draw cadres without any religious bias. Indeed individual news reports point to Maoist groups involved in murder of a Hindu religious leader, admitting that they derive major support from minority communities in Orissa, and noting that “most of the cadre members and supporters in Orissa belonged to Christian community”. They also brand Sangh Parivar as a “fundamentalist” grouping and referred to senior BJP and VHP leaders as their “natural targets”.
Based on the assertion of Maoist outfits it is not so “obvious” that Maoism is synonymous with Hindu terror.
Having established the inherent weakness of writer’s key assertion, I now revisit the terrorist violence data from SATP, which is reported for 2005-15. The data gives us an additional insight, once we account for Hindu and Muslim population shares respectively. As Column 3 above shows, Islamic extremism related violence is highly disproportionate compared to the population share of Muslims (even if we for a second club Left Wing Extremism with Hindutva related extremism).
I sum up my rebuttal to Mr. Patel’s article with three conclusions: a) There is no data to question or support if most terrorists in India are Muslims b) There is no evidence that Hindus are responsible for most terrorism related violence c) Islamic extremism is highly disproportionate to population share of Muslims in India, and maybe that is why it garners more headlines.
 http://www.thenational.ae/news/world/south-asia/maoists-issue-strict-warning-to-hindus#full & http://www.rediff.com/news/2008/oct/05orissa1.htm