Two climate activists from the Last Generation movement flung mashed potatoes on a valuable painting by French impressionist Claude Monet at a museum in the German city of Potsdam, just outside Berlin, on Sunday.
Whether the painting from Monet's "Les Meules" (Haystacks) series had sustained permanent damage still had to be investigated, said Carolin Stranz, a spokesperson for Museum Barberini.
She said the potatoes were quickly removed and the painting was protected by a glass pane.
The two activists wearing high visibility orange vests also glued themselves to the floor, with a total of four people involved in the protest.
Police spokesman Mario Heinemann officers took two people into custody at the museum, which specializes in impressionist paintings. They are being investigated for trespassing and damage to property.
Last Generation published a video of the attack on Twitter, saying the substance thrown at the painting had been potato puree and calling on politicians to take effective measures to limit climate change.
"We make this Monet the stage and the public the audience. If it takes a painting – with mashed potatoes or tomato soup thrown at it – to make society remember that the fossil fuel course is killing us all: Then we'll give you mashed potatoes on a painting!"
Climate activists seem to have developed a liking for foods for their actions, with two demonstrators, albeit from a different movement, arrested in London about a week ago after throwing tomato soup on Vincent Van Gogh's "Sunflowers."
However, only the frame sustained light damages as the image in London's National Gallery was covered by glass.
The painting from Monet's series "Haystacks" hangs in the permanent exhibition of the Museum Barberini from the collection of the founder and multi-billionaire Hasso Plattner.
A few days ago, there were indications that environmental activists could carry out an action in the Barberini, the spokeswoman said. However, security personnel at the time were able to prevent this. She did not provide further details.
