Two climate activists on Saturday each glued a hand to the frames of two paintings by Spanish master Francisco Goya at the Prado museum in Madrid, police said.
The protest did not damage either painting, but the protesters scrawled "+1,5°C" on the wall between the two artworks in reference to the Paris Agreement target of capping warming at 1.5 degrees Celsius above pre-industrial levels.
Both activists were detained, police said.