At the first blare of air raid sirens, the people milling about in a grassy park barely stirred. Five-year-old Tae Sano clung to her mother’s hand. Some of the people around her, all wearing bright-yellow bibs, took a few uncertain steps. But the only real urgency came from a man in a blue uniform, jogging through the confused crowd.

“One more time,” he called out through a megaphone.

When the sirens wailed anew, a voice rang through the park: “A missile was just launched. Please evacuate immediately.”

This time, people moved. Ayako Sano led her three children to a nearby auditorium, where they crouched, hands over their heads, and waited for the drill to end. The exercise, the first for the island city of Ishigaki — closer to China and Taiwan than to the Japanese mainland — is being repeated across the country as increasingly restive neighbors heighten concerns about war.

“Nowadays, you never know what might happen,” Sano, a 37-year-old City Hall employee, said after the drill. “Not just in Ishigaki, but wherever you are in Japan.”

As geopolitical tensions in Asia grow more fraught, Japan has boosted military spending to record highs, and fear has permeated even some of the country’s most remote islands.