A painting by Mark Rothko has been defaced at the Tate Modern art gallery.
Police were called after a small area of the mural piece was painted on Sunday, said a spokeswoman for the gallery.
"Tate can confirm that at 3.25pm this afternoon, there was an incident at Tate Modern in which a visitor defaced one of Rothko's Seagram murals by applying a small area of black paint with a brush to the painting.
"The police are currently investigating the incident," said the spokeswoman.
The gallery was shut for a short period and then reopened.