A rogue graffiti artist casually took out a marker and wrote on a Rothko painting at the Tate Modern gallery in London today. 

Tim Wright tweeted the picture of the altered artwork used above. He said on Twitter that the man was just sitting there and staring at the picture when he abruptly got up, took out a marker and went for it. He described the scene in more detail to the Guardian

"Then we heard the sound of a pen, but by the time we turned around he was pretty much finished with his tag," said Wright, who was with his girlfriend on a weekend visit to London from Bristol. "The pen ink then just dripped down the painting. Once we realised what had happened, we went to find a member of staff. They were really shocked when they came and saw what he had done."

The gallery freaked out, obviously, and briefly went into lockdown after they discovered the defaced painting. 

The perpetrator won't be too hard to find considering he signed his name and left an important clue behind. The new addition to the Rothko appears to read, "Vladimir '12 a potential piece of yellowism," through all the dripping ink. 'Vladimir' is very likely Vladimir Umanets, a visual artist and one half of the Yellowism movement according to their website. "Yellowism is not art or anti-art," according to their manifesto. They're right. It's a publicity stunt.