Up to seven people are feared dead following an explosion at a hydroelectric power plant at a reservoir in northern Italy.
Three men aged between 35 and 73 were found dead at the facility at the Suviana reservoir following Tuesday's blast. At least five workers suffered serious burns.
Four people are still missing on Wednesday more than 24 hours after the accident. Rescue crews said they have all but given up hope of finding anyone else alive.
"We are working without much hope of finding the missing alive," a spokesman for the fire brigade said.
The exact circumstances of the blast are still unclear.
According to initial findings, a fire broke out during work on a turbine at a depth of about 30 metres underground, which led to the explosion.
As a result, water also entered the building, making the rescue work more difficult. The reservoir is located in a regional park in the Apennine Mountains between the cities of Bologna and Florence at an altitude of just under 500 metres above sea level.
According to the rescue services, the lower levels of the facility are partially flooded. The dam itself - about 2 kilometres away - was not affected by the explosion.
The renewable energy company Enel Green Power, which owns the power station, expressed its regrets to the families of the victims.
"The chairman, the CEO, the entire board of directors and the board of statutory auditors of Enel Holding express their deepest condolences to the families of the victims and solidarity with all those involved in the tragic event in Suviana ... and remain close to their colleagues at Enel Green Power," a statement from the firm read.
The firm also thanked firefighters, law enforcement, the civil protection force and the rescuers "for the work they have provided and are continuing to provide at this time."
The dead, whose bodies have already been recovered, have been identified as three men aged between 35 and 73 who were working for subcontractors.
On Wednesday, psychologists at the reservoir were looking after family members who were following the clean-up operation.
Power production was interrupted as a result of the explosion, but according to the operating company, this had no major impact on the region's power supply.
The power plant supplies both the Emilia-Romagna region and Tuscany. It was built back in the 1920-30s. The area around the reservoir is very popular with hikers.
