Making good on their promise last summer to escalate protests against British Petroleum’s sponsorship of arts institutions in the UK, activists, dressed as ice from the melting Siberian permafrost, staged a flash mob in the British Museum’s marble foyer over the weekend, reports Ashitha Nagesh for Metro.co.uk. The group behind the action, BP or Not BP?, sang about the melting ice and the oil company’s “greenwashing” through its sponsorship of the exhibition “Scythians: Warriors of Ancient Siberia,” which focuses on the ancient tribes of nomadic warriors in southern Siberia from around 900 BC to 200 BC. The show opened in September and runs through January 14, 2018. Some visitors to the museum even joined in, and the protesters also displayed a massive flag with the BP logo on it during their demonstration. Large “cracks” made of black paper were applied to the floor, to suggest the disappearing ice.

A representative from the group said that many of the Scythian artifacts on display in the exhibition were preserved by the permafrost, which is melting, in part due to BP’s political lobbying and polluting activities. A British Museum spokeswoman told Metro the following: “The British Museum respects other people’s right to express their views and allows peaceful protest onsite at the museum as long as there is no risk to the museum’s collection, staff or visitors. The long-term support provided by BP allows the museum to plan its programming in advance and to bring world cultures to a global audience through hugely popular exhibitions and their associated public programs.”

In 2016, BP announced they would invest more than $10 million in the British Museum, the National Portrait Gallery, the Royal Opera House, and the Royal Shakespeare Company over the next five years. Both Tate and the Edinburgh International Festival decided not to renew their partnerships with BP last year.