war. In May of that year, Rhee pushed through constitutional amendments which made the presidency a directly-elected position. To do this, he declared martial law, arrested opposing members of parliament, demonstrators, and anti-government groups. Rhee was subsequently elected by a wide margin. Rhee regained control of parliament in the 1954 election, and thereupon pushed through an amendment to exempt himself from the eight-year term limit, and was once again re-elected in 1956. Soon after, Rhee's administration arrested members of the opposing party and executed the leader after accusing him of being a North Korean spy. The administration became increasingly repressive while dominating the political arena, and in 1958, it sought to amend the National Security Law to tighten government control over all levels of administration, including the local units. These measures caused much outrage among the people, but despite public outcry, Rhee's administration rigged the March 1960 presidential election and won by a landslide. On that election day, protests by students and citizens against the irregularities of the election burst out in the city of Masan. Initially these protests were quelled with force by local police, but when the body of a student was found floating in the harbor of Masan, the whole country was enraged and protests spread nationwide. On 19 April, students from various universities and schools rallied and marched in protest in the Seoul streets, in what would be called the April Revolution. The government declared martial law, called in the army, and suppressed the crowds with open fire. Subsequent protests throughout the country shook the government, and after an escalated protest with university professors taking to the streets on 25 April, Rhee submitted his official resignation on 26 April and fled into exile. Second Republic (1960–1963) After the student revolution, power was briefly held by an interim administration under the Foreign Minister Heo Jeong. A new parliamentary election was held on 29 July 1960. The Democratic Party, which had been in the opposition during the First Republic, easily gained power and the Second Republic was established. The revised constitution dictated the Second Republic to take the form of a parliamentary cabinet system where the President took only a nominal role. This was the first and the only instance South Korea turned to a parliamentary cabinet system instead of a presidential system. The assembly elected Yun Po-sun as President and Chang Myon as the Prime Minister and