A huge fire has destroyed part of the 19th Century basilica of Saint-Donatien in the French city of Nantes, the BBC reported.
The blaze broke out on Monday after morning Mass, with worshippers evacuated from the building, Rev Benoit Bertrand told local media.
Around 80 firefighters worked to extinguish the flames, which are believed to have originated on the roof where work was being carried out.
Two workers escaped from the top of the building unharmed.
The roof has been severely damaged and efforts are now under way to save several precious objects inside the basilica, most notably its organ.