STORY: Video from 'Just Stop Oil' shows three protesters stepping over the rope around a flower garden and throwing the paint powder over the plants while telling visitors that they want the government to stop issuing licenses for oil, gas and coal exploration and extraction.
Visitors called for security and shouted "no" at the protesters. One woman sprayed the protesters with water.
Security officials escorted the protesters away and video later showed the police putting them in a police van.
Just Stop Oil, a climate protest group, wants Britain to end all new oil and gas projects and has staged a number of protests including activists throwing soup over Vincent van Gogh’s painting "Sunflowers" at London's National Gallery last October.