TOKYO (AP) — Tokyo Olympic organizers and government officials are preparing for everything, including an earthquake taking place during next year’s games.

They ran a simulation disaster drill at the new Ariake venue that will be the site for gymnastics during the Olympics. Thursday’s drill presumed a 7.3-magnitude earthquake in Tokyo Bay.

Hundreds of firefighters, police, and Japan Self-Defense Force personnel took part. Japan is hit regularly by earthquakes and takes preparedness seriously.

The threat of quakes and the summer heat are the major worries as organizers prepare to open the Olympics on July 24.