Senanayake became the first Prime Minister of Sri Lanka. In 1949, with the concurrence of the leaders of the Ceylon Tamils, the UNP government disenfranchised the Indian Tamil plantation workers. This was the price that Senanayake had to pay to obtain the support of the Kandyan Sinhalese, who felt threatened by the demographics of the tea estates where the inclusion of the "Indian Tamils" would have meant electoral defeat for the Kandyan leaders. Senanayake died in 1952 after falling from a horse and was succeeded by his son Dudley Senanayake, the then minister of Agriculture. In 1953 he resigned following a massive Hartal ("general strike") by the Left parties against the UNP. He was followed by John Kotelawala, a senior politician and an uncle of Dudley Senanayake. Kotelawala did not have the enormous personal prestige or the adroit political acumen of D. S. Senanayake. He brought to the fore the issue of national languages that D. S. Senanayake had adroitly kept on the back burner, antagonising the Tamils and the Sinhalese by stating conflicting policies with regard to the status of Sinhala and Tamil as official languages. He also antagonized the Buddhist lobby by attacking politically active Buddhist Monks who were Bandaranaike's supporters. In 1956, the Senate was abolished and Sinhala was established as the official language, with Tamil as a second language. Appeals to the Judicial Committee of the Privy Council in London were abolished and plantations were nationalised to fulfil the election pledges of the Marxist program and to "prevent the ongoing dis-investment by the owning companies". In 1956, the Sinhala Only Act came into being. This established Sinhala as the first and preferred language in commerce and education. The Act took effect immediately. As a consequence vast numbers of people, mostly Burghers, left the country to live abroad as they felt discriminated against. In 1958, the first major riots between Sinhalese and Tamils flared up in Colombo as a direct result of the government's language policy. 1971 Uprising The leftist Sinhalese Janatha Vimukthi Peramuna drew worldwide attention when it launched an insurrection against the Bandaranayake government in April 1971. Although the insurgents were young, poorly armed, and inadequately trained, they succeeded in seizing and holding major areas in Southern and Central provinces before they were defeated by the security forces. Their attempt to seize power created a major crisis for the government and forced a fundamental reassessment