Rescuers search for 4 still missing after a deadly explosion rocked an Italian hydroelectric plant

Search and rescue operations were underway Wednesday at a hydroelectric plant close to the northern Italian city of Bologna after a devastating blast killed at least three workers, injured five, and left four missing.

Dozens of firefighters and divers searched overnight following the massive explosion Tuesday afternoon that rocked the plant at about 40 meters (130 feet) below the water level, causing the collapse of structural parts and flooding.

“We are working, but with a few hopes of finding missing people alive. … The scenario we are facing doesn’t give us this impression,” said Luca Cari, a spokesperson for Italian firefighters, said Wednesday. “We are working in very complex and difficult conditions. The floor hit by the explosion was dry and now has 50 centimeters (19 inches) of water. We are reconsidering the intervention and evaluating safety considerations.”

The explosion at energy company Enel Green Power’s Bargi plant, south of Bologna, happened during maintenance work and collapsed part of the nine-story underground structure. A fire broke out when a turbine exploded on the eighth floor below the surface, flooding the floor below, Bologna Prefect Attilio Visconti said.

The three men who died in the explosion were identified as workers between 35 and 73, local media reported. According to the first reconstructions of the accident by witnesses and survivors, the blast happened during a testing operation that involved about 15 workers, almost all employees of three external companies hired by Enel.

Local prosecutors are expected to launch a probe Wednesday.

Marco Masinara, the mayor of the nearby town of Camugnano, said the structure was “a historic power plant for us,” providing jobs for many families.

“Until today, nothing ever happened. Today, a drama occurred. Our world collapsed,” he said Tuesday, adding that three of the injured were in serious condition.

The artificial Suviana Lake was formed by the construction of a dam from 1928-32, and is located in a regional park. Enel Green Power said in a statement Tuesday that there was no damage to the dam.

The string of recent accidents on worksites across Italy has fueled concerns by trade unions about workplace safety in the country. Two of the country’s largest unions were already planning to hold a 4-hour nationwide strike Thursday.

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