Mona Lisa Béroud checked back with the Section Chief of the Louvre who confirmed that the "Mona Lisa" was not with the photographers. The Louvre was closed for an entire week during the investigation. French poet Guillaume Apollinaire came under suspicion and was arrested and imprisoned. Apollinaire implicated his friend Pablo Picasso, who was brought in for questioning. Both were later exonerated. Two years later the thief revealed himself. Louvre employee Vincenzo Peruggia had stolen the "Mona Lisa" by entering the building during regular hours, hiding in a broom closet, and walking out with it hidden under his coat after the museum
Louvre building was occupied by the Académie des Inscriptions et Belles-Lettres and the Académie Royale de Peinture et de Sculpture, which in 1699 held the first of a series of salons. The Académie remained at the Louvre for 100 years. During the French Revolution, the National Assembly decreed that the Louvre should be used as a museum to display the nation's masterpieces. The museum opened on 10 August 1793 with an exhibition of 537 paintings, the majority of the works being royal and confiscated church property. Because of structural problems with the building, the museum was closed in 1796 until 1801.