An unknown number of people are trapped inside a shopping mall that sustained severe damage following a powerful 7.1-magnitude earthquake that struck southwestern Japan on Tuesday. The Guardian reported.

“In Kashima town, the second floor of a shopping complex collapsed, leaving numerous people trapped inside,” the local fire department said in an official statement.

Police officials earlier reported receiving alerts regarding a sound resembling an explosion at the Aeon Mall branch in the Kumamoto region. However, authorities have yet to confirm the full extent of the damage or provide details on casualties.

According to the Japan Meteorological Agency (JMA), the earthquake struck Kumamoto prefecture at 4:27PM local time at a shallow depth of 10 kilometers.

The agency noted that the tremor registered the maximum intensity of seven on Japan’s Shindo seismic scale. Although a tsunami advisory for a one-meter wave was initially issued, the agency subsequently lifted the warning.

The region has a history of severe seismic activity. In 2016, Kumamoto was hit by twin devastating earthquakes, measuring 6.5 and 7.3 in magnitude, which claimed 273 lives and left more than 2,800 people injured.