Climate protesters threw soup over Vincent van Gogh’s “Sunflowers” in London’s National Gallery on Friday to protest fossil fuel extraction.

The group Just Stop Oil which wants the British government to halt new oil and gas projects, said activists dumped two cans of Heinz tomato soup over the oil painting, one of the Dutch artist’s most iconic works.

London’s Metropolitan Police said officers arrested two people on suspicion of criminal damage and aggravated trespass.

The group has drawn attention, and criticism, for targeting artworks in museums. In July, Just Stop Oil activists glued themselves to the frame of Leonardo da Vinci’s “The Last Supper” at London’s Royal Academy of Arts, and to John Constable’s “The Hay Wain” in the National Gallery.

Activists have also blocked bridges and intersections across London during two weeks of protests.

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