The Taiwanese fire department on Thursday said a suspected gas explosion at a department store in the central city of Taichung killed no fewer than four people and injured 24 others.

In a statement, the fire department said the blast occurred on the 12th floor of the building, where construction was taking place, with damage starting from the 9th floor.

According to the statement, the food court of the Taichung Shin Kong Mitsukoshi department store on the 12th floor was closed at the time due to the building work.

The health ministry said that one of the injured was in the intensive care unit of the hospital.

Writing on his Facebook page, Taiwan’s President Lai Ching-te called for a speedy investigation into the cause of the blast.