Japan is hosting a multinational security exercise off Tokyo's southern coast aimed at intercepting shipments of missiles and other weapons of mass destruction at sea.
Japanese navy sailors and their counterparts from the US and Australia and the South Korean coast guard joined today's exercise. Participants took turns stopping and raiding a target boat found at sea.
Journalists observed from the Japanese destroyer Murasame.
Thirty countries, including six core members of the Proliferation Security Initiative, participated, along with 20 observers and four non-members.
The initiative started in 2003 as part of Washington's effort to block shipments of nuclear, chemical and biological weapons, as well as missiles to carry them. The initiative does not target any specific country, but North Korea has criticised it in the past.