Emergency services are still searching for the four people missing in the explosion that occurred yesterday at a hydroelectric power station on Lake Soviana, south of the Italian city of Bologna.

At least three employees died in the accident. Five people were injured. They were transported to the hospital by air ambulance. Three of them are in critical condition.

The search for the missing continued throughout the night. This is not an easy task: the explosion occurred forty meters underground and caused a fire and floods.

Rescue workers are still hoping to find survivors:

Fire Chief Francesco Notaro told Italian news channel Sky TG24 that part of the nine-storey building had collapsed. Divers were deployed to find the missing people.

The hydroelectric power station has been undergoing major maintenance for nearly a year to modernize the turbine. The plant was tested for the first time yesterday.

It was immediately clear that things were not going well. One employee told La Repubblica newspaper that he heard a “metallic sound” from the ground floor, similar to the sound of a large engine revving, then an “explosion.” From the ground floor he saw “a terrifying sea of ​​fire rising.”

The cause of the explosion is still under investigation. La Repubblica newspaper wrote that it could not be ruled out that the explosion was the result of human error.

The five injured suffered serious burns. It was so hot that some people’s gloves melted in their hands. Emergency services had to cut off their clothes to free them. Because the employees were still in shock, the police would not question them until later.

Italian Prime Minister Meloni said she was following the “terrible” news. She expressed her support for the victims and their families.

Enel Green Power, the company behind the plant, stated that there was no damage to the dam in which the plant is located. The company also expresses its condolences to the victims and their families.