A medieval tower in central Rome that was under renovation partially collapsed on Monday, with one worker trapped alive under rubble, authorities said.

Part of the Torre dei Conti collapsed just after 11:30 am (1030 GMT), sending rubble into the street and a thick white cloud of dust into the air.

"It's a very complex situation for the firefighters because there is a person trapped inside," Rome Prefect Lamberto Giannini told reporters.

The trapped worker, a Romanian national, was "conscious", the Romanian foreign ministry said.

Three other workers were evacuated from the site, one of them in a critical condition, a spokesman for the fire service told AFP.

The tower is in a busy area, just off the Imperial Forum and close to the Colosseum, Italy's top tourist site.

Rome Mayor Roberto

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