Japan's coast guard on Friday held a joint exercise with counterparts from the United States and the Philippines, as the three Pacific nations beef up defense cooperation in the face of China's expanding maritime activities.

Helicopters buzzed in the shadow of a smouldering volcano and boats rescued dummies from the sea this week in a show of maritime unity by Japan, the United States and the Philippines.Tensions between China and other claimants to parts of the East and South China Seas have pushed Japan to deepen ties with the Philippines and the United States.