From the guardian.co.uk:
Artists, musicians and green activists plan to step up protests against BP's sponsorship of Britain's most prestigious galleries and museums in the wake of the Gulf oil catastrophe.
A group calling itself Good Crude Britannia, made up of artists, poets, writers and filmmakers, will picket Tate Britain's summer party next Monday which is billed by the gallery as celebrating 20 years of BP's sponsorship.
Late in the article:
Last month a group called Liberate Tate entered the gallery's main turbine hall and released dozens of black balloons attached to dead fish in protest against the Gulf oil spill. Gallery staff had to shoot the balloons down with air rifles.