The maximum number — 40 — operate in Manipur, followed by 36 in Assam, 32 in Jammu and Kashmir, and 30 in Tripura, figures compiled by the South Asia Terrorism Portal say.
Punjab is home to 12 terror groups, Meghalaya houses four, Nagaland three, Mizoram two and Arunachal Pradesh one.
The list also includes pan-India Left-wing groups like the People's War Group and the Communist Party of India-Maoist, as also other extremist groups like the Students Islamic Movement of India (SIMI) and the Deendar Anjuman.
The following is a thumbnail sketch of the various terror groups operating in India:
Assam: 36 groups. Prominent among them are United Liberation Front of Asom (ULFA), National Democratic Front of Bodoland (NDFB), Kamtapur Liberation Organisation (KLO), Karbi National Volunteers (KNV), Harkat-ul-Mujahideen, Harkat-ul-Jehad.
Jammu & Kashmir: 32 groups. Prominent among them are Hizbul Mujahideen, Harkat-ul-Ansar (now known as Harkat-ul Mujahideen), Lashkar-e-Taiba (LeT), Jaish-e-Mohammad Mujahideen E-Tanzeem, Al Badr, Muslim Janbaz Force and Ikhwan-ul-Mujahideen.
Punjab: 12 groups. Prominent among them are Babbar Khalsa International (BKI), Khalistan Zindabad Force (KZF), Khalistan Commando Force (KCF), Bhindrawale Tigers Force of Khalistan (BTFK) and Dashmesh Regiment.
Manipur: 40 groups. Prominent among them are United National Liberation Front, People's Liberation Army, People's Revolutionary Party of Kangleipak (Prepak) — all of which now operate from the unified platform of the Manipur People's Liberation Front (MPLF), Kangleipak Communist Party (KCP) and Kuki National Front (KNF).
Proscribed Terrorist/Insurgent Groups
Kangleipak Communist Party (KCP)
Kanglei Yawol Kanna Lup (KYKL)
Manipur People's Liberation Front (MPLF)
People's Liberation Army (PLA)
People's Revolutionary Party of Kangleipak (PREPAK)
United National Liberation Front (UNLF)
Active Terrorist/Insurgent Groups
Hmar People's Convention- Democracy (HPC-D)
Kuki Liberation Army (KLA)
Kuki National Army (KNA)
Kuki National Front (KNF)
Kuki Revolutionary Army (KRA)
National Socialist Council of Nagaland -- Isak-Muivah (NSCN-IM)
People's United Liberation Front (PULF)
United Kuki Liberation Front (UKLF)
Zomi Revolutionary Army (ZRA)
Inactive Terrorist/ Insurgent Groups
Chin Kuki Revolutionary Front (CKRF)
Hmar People's Convention (HPC)
Hmar Revolutionary Front (HRF)
Indigenous People's Revolutionary Alliance (IRPA)
Iripak Kanba Lup (IKL)
Islamic Revolutionary Front (IRF)
Islamic National Front (INF)
Kangleipak Kanba Kanglup (KKK)
Kangleipak Liberation Organisation (KLO)
Kom Rem People's Convention (KRPC)
Kuki Defence Force (KDF)
Kuki Independent Army (KIA)
Kuki International Force (KIF)
Kuki Liberation Front (KLF)
Kuki National Organisation (KNO)
Kuki National Volunteers (KNV)
Kuki Revolutionary Front (KRF)
Kuki Security Force (KSF)
Manipur Liberation Tiger Army (MLTA)
North East Minority Front (NEMF)
People's Republican Army (PRA)
Revolutionary Joint Committee (RJC)
United Islamic Liberation Army (UILA)
United Islamic Revolutionary Army (UIRA)
Zomi Revolutionary Volunteers (ZRV)
Tripura: 30 groups. Prominent among them are National Liberation Front of Tripura, All Tripura Tiger Force (ATTF) and Tripura Liberation Organisation Front.
Nagaland: Three groups — National Socialist Council of Nagaland (Isak-Muivah), National Socialist Council of Nagaland (Khaplang) and Naga National Council (Adino).
Meghalaya: Four groups — Hynniewtrep National Liberation Council (HNLC), Achik National Volunteer Council, People's Liberation Front of Meghalaya and Hajong United Liberation Army.
Mizoram: Two groups — Bru National Liberation Front and Hmar People's Convention-Democracy.
Arunachal Pradesh: Arunachal Dragon Force