The US military is conducting a large-scale field training exercise in the Pacific region, including bases in Japan for the first time.

The US Indo-Pacific Command holds the exercise, Valiant Shield, every two years in Guam and elsewhere in the Pacific, involving the US Army, Navy, Air Force, Marine Corps, and other forces.

The 10th Valiant Shield that is taking place from June 7 to 18 is being conducted under a multinational framework for the first time. It covers a wider area than previous exercises.

On Thursday, three F-16 fighter jets based on the US mainland were seen arriving at the Hachinohe Air Base of Japan's Maritime Self-Defense Force in Aomori Prefecture.

Two other F-16s from the US mainland also landed at the Matsushima Air Base of the Air Self-Defense Force in Miyagi Prefecture.

Japan's Defense Ministry explains that the US fighter jets were involved in a drill designed to prepare them for a contingency in which a US air base in Japan came under attack and became unusable. In that case, the US fighters would be deployed to SDF bases instead.

The two Japanese air bases involved in the exercise are home to SDF fighter jets and reconnaissance planes. But it is believed this is the first time that US fighter jets have landed there as part of a training exercise.

Valiant Shield 2024 has seen the US military and the SDF holding joint drills in other locations in the country, such as Hokkaido, Kyushu, and the Pacific island of Ioto.

Analysts say the US decision to conduct part of the biennial exercise in Japan is aimed at strengthening its rapid-response capability in the event of a military contingency situation in areas surrounding Japan, apparently with China in mind.