were they declared as a terrorist organization?
Yes, 32 countries currently list the LTTE as a terrorist organisation.
Liberation Tigers of Tamil Eelam
32 countries currently list the LTTE as a terrorist organisation.
how many tamils are there in sri lanka 70% since how long have they been living here? Sri Lankan Tamils have a very long history in Sri Lanka and have lived on the island since at least around the 2nd century BCE. are they genetically linked to other sri lankans? Yes,  genetic studies indicate that they are closely related to the Sinhalese ethnic group in the island. which religion do they follow? The Sri Lankan Tamils are mostly Hindus with a significant Christian population. was there any militancy related to them? Yes, Liberation Tigers of Tamil Eelam (LTTE) what was its goal? Its aim was to secure an independent state of Tamil Eelam
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Liberation Tigers of Tamil Eelam [SEP] Proscription as a terrorist group
32 countries currently list the LTTE as a terrorist organisation. As of October 2019, these include: The first country to ban the LTTE was its brief one-time ally, India. The Indian change of policy came gradually, starting with the IPKF-LTTE conflict, and culminating with the assassination of Rajiv Gandhi. India opposes the new state Tamil Eelam that LTTE wants to establish, saying that it would lead to Tamil Nadu's separation from India, despite the leaders and common populace of Tamil Nadu considering themselves Indian. Sri Lanka itself lifted the ban on the LTTE before signing the ceasefire agreement in 2002.