At least 4 dead in explosion at hydroelectric plant in Italy’s Bologna

Rescue efforts underway to find missing people following blast at plant

A general view shows the Enel hydroelectric power plant after a fatal explosion and fire, in Bargi, Italy (EPA)

At least four people died and five others sustained injuries in an explosion at a hydroelectric plant in northern Italy.

Four people were unaccounted for following Tuesday's explosion at the decades-old plant near Bologna, said regional fire chief Francesco Notaro.

The explosion took place at power company Enel's Bergi plant during maintenance work, which led to the collapse of part of the nine-story underground structure. The incident provoked a fire and caused flooding at depths of up to 60m, Mr Notaro told SKY TG24.

The fire brigade said earlier that an explosion had occurred around 3pm (local time) at a dam on Lake Suviana, one of three artificial lakes that feed the power station.

Rescuers work at the scene of an explosion that occurred in a hydroelectric power plant on the Lake Suviana reservoir (EPA)

Search efforts were proceeding with care due to the risk of additional collapsing, he said, adding that the divers were aiding the search, which went through the night.

"Our world collapsed," said Marco Masinara, the mayor of the nearby town of Camugnano. "This is a historic power plant for us. It has been managed by Enel for 50 years, providing jobs for many families," the mayor told the broadcaster.

"Until today, nothing ever happened."

Three of the people who died were aged between 35 and 73, according to reports. Three people were rushed to the hospital with serious injuries, the fire chief said.

A firefighter works at the site after a blast at a hydroelectric power plant in Bargi, Italy (VIA REUTERS)

Video provided by firefighters showed smoke rising from underground at the lakeside power plant.

A diver involved in the search and rescue operation said he reached the seventh floor below the surface but could not get hold of the three people trapped further down.

Giuseppe Amato, the city's chief prosecutor, said an investigation would be launched once the plant was declared safe and the missing people were found.

The artificial Suviana Lake was formed by the construction of a dam from 1928-32 and located in a regional park at an altitude of 500m, some 70km southwest of Bologna.

Enel Green Power said in a statement that there was no damage to the dam as chief executive Salvatore Bernabei traveled to the site to follow developments. The company expressed condolences to the victims and their families.

Prime minister Giorgia Meloni said she was following the "terrible" news and expressed solidarity with the victims and their families.

"Thanks to the firefighters who promptly intervened, to the rescuers and to those who are working in these hours in the search for the missing," she said on X.

In a high profile accident in February, five workers were killed and three seriously injured while building a supermarket in the city of Florence.