A person seemingly disguised as an old woman in a wheelchair has staged an attack on the Mona Lisa.
Video shared online shows the world’s most famous artwork with cake smeared across the glass case protecting it.
Bystanders said a "man dressed as an old lady" jumped out of a wheelchair at the Louvre in Paris before attempting to smash the protective glass in front of the Leonardo da Vinci painting.
The gallery explained the culprit had managed to get close to the portrait by "simulating a disability", allowing them to take advantage of a policy designed to help people with mobility problems see the major works in its collection clearly.
One witness said the person then proceeded to "smear cake on the glass and throw roses everywhere before being tackled by security".
Separate footage shows the person suspected of being responsible telling bystanders in French: "Think of the planet… there are people who are destroying the planet, think about that … That’s why I did it."
Apparently wearing lipstick and a wig, the person is then escorted away by security before they were handed over to police.
The Louvre said the painting, considered an archetypal masterpiece of the Italian Renaissance, was not damaged.
"A visitor simulated a disability to use a wheelchair and approach the work installed in a secure display case," spokeswoman Marion Benaiteau told Sky News.
"The Louvre had applied its usual procedures for people with reduced mobility, allowing them to admire this major work."
Once near the painting, she said "this individual threw on the glass of the Mona Lisa a pastry that he had hidden in his personal effects".
"This cake had no effect on the painting, which suffered no damage," Ms Benaiteau added.
"The individual was immediately seized and evacuated by the reception and surveillance agents and then handed over to the police. The Louvre Museum filed a complaint."
She said the museum "salutes the professionalism of its agents who reacted immediately during this incident".