Yoshihide Suga, Japan’s Chief Cabinet Secretary, branded the situation "a grave, unprecedented threat" while Prime Minister Shinzo Abe called on the UN to convene an emergency meeting of member states.

The threat of nuclear warfare erupting in East Asia remains very real and North Korea's latest exploits over the Sea of Japan indicate a further advance in the rogue state's ballistic capabilities as it seeks to develop an intercontinental missile capable of carrying a warhead.

But how real is the threat to Japan and to Hokkaido in particular? Where is the island and what is life like there?

Hokkaido is Japan's northernmost island, lying just 27 miles from Russian soil and east of the disputed Kuril Islands.

It covers 32,221 square miles and is separated from Japan's largest landmass, Honshu, by the Tsugaru Strait and connected by an undersea railway line via the Seikan Tunnel. Its terrain is mountainous, particularly at the heart of the island, causing it to be less developed than much of the rest of the country. The capital city, Sapporo, is its biggest conurbation.

The island is seismically active and was badly damaged by a tsunami in 1993, when 202 people were killed when a wave triggered by a 7.7 magnitude earthquake lashed Okushiri.

Hokkiado is generally well known for its inhospitable climate, comprising harsh snowy winters, sub-zero temperatures and frozen seas.

During the Second World War, Hokkaido was largely spared from allied bombing but did come under attack from the US Navy, seeking to disable its shipping and military capabilities. Its southern ports were severely damaged by US aircraft in raids on 14 and 15 July 1945 as war in the Pacific ended in defeat for Imperial Japan.

Modern day Hokkaido has a population of approximately 5.4 million people. Its economy is dominated by the service sector, with agriculture and tourism also playing a key role.

In pictures: North Korea military drill Show all 8 1 /8 In pictures: North Korea military drill In pictures: North Korea military drill North Korea's leader Kim Jong Un watches a military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) is seen in this handout photo by North Korea's Korean Central News Agency (KCNA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) is seen in this handout photo by North Korea's Korean Central News Agency (KCNA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) KCNA/Handout via REUTERS In pictures: North Korea military drill A military drill marking the 85th anniversary of the establishment of the Korean People's Army (KPA) KCNA/Handout via REUTERS In pictures: North Korea military drill This image made from video of still images broadcast in a news bulletin by North Korea's KRT, shows what was said to be a 'Combined Fire Demonstration' held to celebrate the 85th anniversary of the North Korean army, in Wonsan, North Korea. KRT via AP Video In pictures: North Korea military drill This image made from video of still images broadcast in a news bulletin by North Korea's KRT, shows what was said to be a 'Combined Fire Demonstration' held to celebrate the 85th anniversary of the North Korean army, in Wonsan, North Korea. KRT via AP Video In pictures: North Korea military drill This image made from video of still images broadcast in a news bulletin by North Korea's KRT, shows what was said to be a 'Combined Fire Demonstration' held to celebrate the 85th anniversary of the North Korean army, in Wonsan, North Korea. KRT via AP Video

A quiet and largely peaceful locale, Hokkaido's people have long lived with the threat posed to their way of life by the natural world.