Japan's defence chief on April 22 ordered troops to activate missile interceptors and get ready to shoot down fragments from a North Korean satellite that may fall on the Japanese territory.
North Korea's leader Kim Jong Un said earlier this week that its first military spy satellite that will be launched at an unspecified date.
North Korea has test-fired about 100 missiles since early last year, saying it was responding to joint U.S.-South Korean military drills that it calls an invasion rehearsal.
Several of the missiles flew over Japan or landed off the northern Japanese coast.
Last week, North Korea test-launched a solid-fuelled intercontinental ballistic missile for the first time.
Defense Minister Yasukazu Hamada on Saturday instructed troops to ready PAC-3 surface-to-air missiles in southwestern Japan, including Okinawa and nearby islands, in an area believed to be under a flight path of a North Korean rocket that will carry the satellite.
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He also ordered the deployment of destroyers equipped with SM-3 ship-to-air missiles to coastal waters, according to a ministry statement.
“We are making the necessary preparation because of a possibility of issuing an order to destroy ballistic missiles and other objects,” the ministry said.
An order to fire missiles has to be approved by the Prime Minister.
North Korea is expected to carry out more weapons tests as the United States and South Korea continue their joint air exercise into next week.
