was he impeached?
Yes, He  faced an impeachment in parliament led by his two formidable rivals in the UNP, Lalith Athulathmudali and Gamini Dissanayake.
Ranasinghe Premadasa
In September 1991, Premadasa faced an impeachment in parliament led by his two formidable rivals in the UNP, Lalith Athulathmudali and Gamini Dissanayake. 
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 were they declared as a terrorist organization? Yes, 32 countries currently list the LTTE as a terrorist organisation. did they carry out any suicide attacks? Yes, their mission included carrying out suicide attacks against enemy targets. did the assassinate anyone? Yes, Ranasinghe Premadasa, Rajiv Gandhi who was the first person mentioned? Sri Lankan president
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Ranasinghe Premadasa [SEP] Impeachment
In September 1991, Premadasa faced an impeachment in parliament led by his two formidable rivals in the UNP, Lalith Athulathmudali and Gamini Dissanayake. He defeated it by adjourning Parliament and the Speaker Mohamed dismissed the impeachment stating a lack of signatures after several of the parliamentarians who supported it withdrew their support after facing threats. He then expelled Athulathmudali and Dissanayake from the party, who then joined to form the Democratic United National Front (DUNF). In 1992, he changed the country's name in English from Sri to Shri Lanka on the advice of soothsayers, who predicted it would improve the country's fortunes.