Vincent Van Gogh’s 1888 masterpiece “Sunflowers” painting, one of the Dutch artist’s most iconic works estimated to be worth around $81 million.

The two people behind the move have been arrested after opening up two cans of Heinz tomato soup and splattering it across the work of art at London’s National Gallery. The suspects are part of a group called “Just Stop Oil,” which has been pushing the British government to halt new oil and gas projects and asking the question, “What is worth more: art or life?”

While the group has drawn international attention over the past few months, they have faced criticism over their tactics of targeting famous works of art.

In July, members of the group glued themselves to the frame of Leonardo Da Vinci’s “The Last Supper” at London’s Royal Academy of Arts. They did the same thing to John Constable’s “The Hay Wain” painting at the National Gallery.

The wave of demonstrations comes as the British government opens new licensing rounds to explore oil and gas in the North Sea, despite criticism from environmentalists and scientists who say the move undermines the country’s commitment to fighting climate change.

National Gallery officials say the activists, who added a splash of tomato red to Van Gogh’s “Sunflowers,” caused only minor damage to the frame of the painting, which was protected by glass. The painting has been put back in display.