According to the Global Terrorism Index 2014, prepared by Institute for Economics and Peace (IEP), the number of attacks also increased with 55 more incidents in 2013 than in 2012.
"Terrorism increased by 70 per cent in India from 2012 to 2013, with the number of deaths increasing from 238 to 404," it said.
However, the majority of terrorist attacks in India have low casualties. In 2013, around 70 per cent of attacks were non-lethal. There were attacks by 43 terrorist groups who can be categorised into three categories - Islamists, separatists and Communists.
"Police are overwhelmingly the biggest targets of Maoists, accounting for half of all deaths and injuries. This is mainly through armed assaults, which killed 85, and bombings and explosions, which killed 43," it said.
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Kidnapping is also a common tactic of Maoists where it is often used as political tool to force the governments to release prisoners.
IEP, which has offices in Sydney, New York, and Oxford, works with a wide range of partners internationally and collaborates with intergovernmental organisations on measuring and communicating the economic value of peace.
In September, al Qaeda announced a presence in India, hoping to unite other Islamist groups, the Index said.
The northeast has seen continual ethno-political unrest from ethnic secessionist movements in the past three decades.
Separatist groups including in Assam and Meghalaya were responsible for 16 per cent of deaths.
"Targeting private citizens, police and businesses, attacks are generally restricted to the geographic region as most of these groups are relatively small and have local claims," the Index said.