A recently unveiled portrait of King Charles was vandalized in a London gallery on Tuesday by an activist animal rights group, the group said.

Two of the group's supporters "pasted the face of the iconic British character Wallace over His Majesty’s," the group said in a press release, referencing a character from "Wallace and Gromit," an animated film series. The group released a video of the vandalization on social media.

Charles last month became the royal patron of the RSPCA Assured charity, which works to improve the lives of animals on farms. And the activist group on Tuesday said its action was part of an effort to stop the "awful suffering across farms being endorsed by the RSPCA."