The owners of a Rotherham steelworks have promised a full investigation will be carried out after explosions at the plant were heard across the town.
Firefighters were called to Liberty Speciality Steels, off Aldwarke Lane, Rotherham, at around 10.30pm on Wednesday.
Residents living close to the site and as far away as Mexborough reported hearing around three blasts.
They dialled 999 fearing for the safety of steel workers but firefighters deployed to the scene carried out checks and established that the sound of the explosion was down to the manufacturing process.
In a statement, Liberty said heavy rain had accumulated in a pit, which caused a ‘violent reaction’ when a large bucket of molten slag was tipped into it.
The firm said: “People around the area heard a loud bang on Wednesday night. This was caused by a violent reaction when a large bucket of molten slag – a by-product of the liquid steel making process – was tipped into the designated pit or lagoon and came into contact with accumulated water, which we believe was caused by recent heavy rain.
“Such a reaction is a rare occurrence but we have a well-established safety procedure to manage such risks and protect our people.
“On this occasion, it was not necessary to activate the procedure as the reaction was contained within the pit and posed no threat to any personnel.
“For safety reasons, the pit is located 500m from the nearest building and vehicles are heavily reinforced to protect the operator.
“We have strict controls in place and all employees are trained in managing situations where molten metal or slag come into contact with water.
“Nevertheless, we take each incident very seriously and a full investigation is being undertaken by the contract company responsible for the slag tipping process.
“The Environment Agency has been informed in line with procedure.
“We apologise for any alarm caused to residents who heard the bang.”
South Yorkshire Police said it ‘received reports of loud bangs heard throughout the Rotherham area’.
The force said there was ‘no cause for alarm’.
Steel firm Liberty bought the Aldwarke Lane plant in May 2017 from Tata Steel as part of £100 million deal to acquire the speciality steel division – protecting jobs at Rotherham, Stocksbridge and Brinsworth in South Yorkshire.