North Korea has fired a ballistic missile over Japan, the fifth launch in 10 days, amid expectations that it is gearing up to test its first nuclear weapon in five years, according to Al Jazeera.

Japan activated its missile warning system and urged people in two northern regions of the country to take shelter early Tuesday.

The missile reached a distance of 4,500 km, the longest ever traveled by a North Korean missile, Japan’s Defense Minister Yasukazu Hamanda said.

South Korean President Yoon Suk-yeol called the launch a “provocation” that violated UN regulations. Japanese Prime Minister Fumio Kishida condemned what he called a “barbaric” act, while the US State Department said the “reckless and dangerous launch” posed “an unacceptable threat to the Japanese public”.

South Korean and US fighter jets have carried out precision bombing drills in response to the missile.