What is the history between the North and South Korea tensions, and why is there current tension?

Tensions between North and South Korea have sharply risen, as North Korea yesterday accused the South of behaving like a “mongrel dog”.

The comments came after North Korea blew up a liason office on its side of the border intended to improve communication with the South, amid a row over anti-Pyongyang propaganda from defectors to the South.

The two countries have been divided for more than 70 years, since the end of the Second World War.

Here, we take a look at past conflict between North and South Korea, and the cause of the present tension.

North and South Korea were joined in a unified Korea for centuries, ruled by monarchs.

However after the Russo-Japanese war of 1905, Korea became occupied by Japan, and formally annexed in 1910.

Korea was ruled by Japan for 35 years, until the end of the Second World War in 1945.

When the war ended, the USSR and the United States divided Korea into two zones: North and South Korea.

The Soviet army set up a communist regime in North Korea, while the United States supported a military government formed in South Korea.

While most working-class people remained in North Korea, many middle-class Koreans fled to the South Korea.

In 1948, the United States called for a vote for all Koreans over the future of the peninsula.

When North Korea refused to participate in the vote, the South formed its own government in Seoul. After the North refused to participate, the South formed its own anti-communist government in Seoul.

Meanwhile, the North installed the premier of the Democratic People’s Republic of Korea (DPRK) in the capital of Pyongyang.

The Korean War began in 1950 when North Korea – supported by the Soviet Union and China – invaded South Korea. South Korea, aided by the United Nations, and principally the US military, which dropped hundreds of bombs on the North, fought back. The conflict lasted three years and killed approximately 3 million people. In 1953, the fighting ended when the Korean Armistice Agreement was signed, creating the Korean Demilitarised Zone (DMZ) which separates the two states, and allowing prisoners to return.