The museum confirmed it was closing for the day "for exceptional reasons," without providing further details.
French media reports say jewellery has been stolen, after three masked men reportedly used a freight lift under renovation to access the Apollo Gallery, where what remains of France's crown jewels are kept.
The gallery is on the side of the River Seine. The thieves are said to have broken windows to gain entry before escaping on motor scooters. They also had chainsaws. The value of the stolen items is not yet known.
