Lance Wakeling, Mary Richardson, Velázquez’s The Rokeby Venus. Part of the Vandalized Paintings Set.
From the Wikipedia article on Mary Richardson:
Mary Richardson’s attack on the painting took place around 11 a.m. on 10 March 1914. A slight woman wearing a tight gray skirt and a coat had stood for some time in front of the Rokeby Venus, apparently in deep contemplation of the painting, when she suddenly smashed the protective glass in front of the canvas, and began “hacking furiously at the picture with a chopper which, it is assumed, she had concealed under her jacket.” When she was apprehended by a guard on duty in the room, she calmly surrendered and allowed herself to be led to the inspector’s office with the words, “Yes, I am a suffragette.”