At least two people have been killed and 26 injured after an explosion at a fuel depot on the outskirts of Florence.
The death toll could rise, however, as three workers at the warehouse owned by Italian energy company Eni remain missing.
The warehouse exploded at around 10.30am, with images showing a towering plume of black smoke rising from the site.
The explosion was so powerful that earthquake monitors picked it up, being an equivalent magnitude of 0.9.
SMS alerts were sent to everyone living within a three-mile radius of the site while 15 companies in the area were evacuated. Locals in Calenzano were urged to keep their windows closed and limit outdoor activities.
An excavator entered the refinery facility to remove debris and help with the search for the workers.
The search for the missing will resume tomorrow morning, Italian newspaper Corriere Fiorentino reported.
An initial assessment has found that the explosion may have happened due to a loss of liquid when the tankers were being refilled.
The explosion could have been caused by a spark, however, they add.
Giuseppe Carovani, the mayor of Florence, said he saw ‘total destruction’ when he inspected the ruins.
‘I imagine who was working there and was near or under the charging infrastructure, that must have looked like hell. The situation is indescribable.
A man in his 50s who was injured in the explosion said it felt like a ‘thunder had passed through us.’
He told la Repubblica that he had ‘never seen anything like it in my life.’
The man was among the five injured casualties who were rushed to Santo Stefano hospital in Prato.
He continued: ‘We did not understand what happened, because everything happened in a few seconds.
‘The explosion was so strong that it made us jump several meters inside our office, the windows broke and injured us. It was the most traumatic experience of my entire life. I am still stunned.’
Now an investigation into the incident has been launched, the Prosecutor’s Office said.
Tuscany’s president Eugenio Giani said: ‘All of Tuscany is united in grief over the tragedy that occurred today in Calenzano. Rescue operations are still ongoing in our hospitals.’
The situation at the depot was ‘quickly contained’ by emergency services, he added.
A local worker told La Repubblica: ‘We heard a huge explosion, all the windows shattered and the shelves fell to the ground. We ran out in terror to protect ourselves and understand what had happened. Some people thought they had thrown a bomb, like in war.’
Masks have been distributed to people after thick plumes of smoke and combusted hydrocarbons have begun to dissipate into the air.
A spokesperson for Eni said: ‘Eni confirms that a fire broke out this morning at the fuel depot in Calenzano (Florence) and that the Fire Brigade is working to put out the flames which are confined to the loading shelter area and do not affect the tanks in any way.
‘The impacts and causes are being immediately verified. Updates will follow.’
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