Beijing is fighting to have an artist’s mural promoting independence for Taiwan and Tibet removed from a brick wall in the small town of Corvallis, Oregon.

Two officials from the Chinese Consulate General in San Francisco have written to the mayor of Corvallis about the mural and last week visited the town to lodge a formal complaint.

“As you are aware, the First Amendment of the US Constitution guarantees freedom of speech in this country and this includes freedom of artistic expression,” Corvallis Mayor Julie Manning has told them.