It was not the first time the 500-year-old painting has been attacked
The Mona Lisa has come under attack from a Russian woman who hurled a cup at the world-famous portrait.
Leonardo da Vinci's masterpiece was completely unscathed, as the ceramic mug smashed on bullet-proof glass surrounding the painting.
The incident happened on 2 August and the woman was arrested, said a spokesman for the Louvre Museum in Paris, which houses the artwork.
Paris police said the woman was taken to a psychiatric ward afterwards.
"It looks like it was done by someone who was unhinged and wanted to draw attention to herself," a Louvre spokesman was quoted as saying by the AFP news agency.
The Louvre, the biggest art museum in the world, has thousands of paintings, but its star attraction is the Mona Lisa, known in France as La Joconde.
The 500-year-old portrait was stolen in 1911, but returned to the Louvre after an Italian was arrested for its theft two years later.
It was doused with acid by a vandal in 1956 and later the same year a Bolivian damaged it again by throwing a stone at it.