Three killed, two missing on Florence building site

"Three workers died because of their jobs, in the heart of Florence," said Monia Monni, civil protection officer for Italy's central Tuscany region, calling it an "immense tragedy".

In a statement posted on Facebook, she said three people were in hospital, two of them in a serious but not life-threatening condition, while "firefighters are still searching for two people missing under the rubble".

The accident took place on a site northwest of Florence's main train station, where workers were putting together prefabricated concrete structures for a new Esselunga supermarket.

The company, which owns a chain of supermarkets across Italy, announced it was closing its Florence stores on Monday afternoon as a mark of respect.

Speaking earlier before the confirmation of the deaths, Prime Minister Giorgia Meloni offered her condolences to those affected and prayers for those injured and missing.

"It is another story... of people who go out to work, who simply go out to do their job, and do not come home," she said during a visit to Calabria.

Italy's newspapers regularly carry stories of workers killed on the job, and Friday's incident sparked outrage among trade unions, who called a demonstration in Florence.

"Safety at work must be considered a priority, it is unacceptable that every day we talk about deaths and injuries as if we are at war," said the CGIL union in a statement.

Almost 800 deaths at work were recorded in Italy last year, according to official statistics -- almost 90 percent of them men, and half aged over 50.

According to European Union statistics, Italy recorded 3.17 workplace deaths per 100,000 employed people, above the bloc-wide average of 2.23 but behind France (4.47) and Austria (3.44).

Across the EU, 22.5 percent of all fatal workplace accidents took place within the construction sector.