About 300 staff members participated in an emergency drill at Koshien Stadium this morning.
At around 10:30am, an announcement was made at the stadium that there was an earthquake that measured 6 on the intensity scale (shindo) and that a tsunami warning was in effect. Staff had to walk around in the stands asking spectators to remain calm and await additional orders. They also had to direct spectators outside of the stadium to evacuate toward high ground in the north. Stretchers and various other emergency equipment were prepared outside of the stadium.
According to Koshien Stadium, emergency drills are held every year before before the spring and summer high school tournaments. The stadium has also been reinforced over the years to withstand large earthquakes.
Source: Nikkan Sports 3/19/2013