A 29-year-old construction worker from Tarxien is in danger of dying from injuries caused when the roof of a residence in Swieqi collapsed, the police said.
The incident happened this morning as the worker and another man from Birkirkara were working on the building.
The roof collapse brought down a lower ceiling.
The two men were assisted by a medical team from Mater Dei Hospital. Officials from the Occupational Health and Safety Unit also went on site.
Magistrate Antonio Mizzi is holding an inquiry.