The Hackney Council had workers paint over an East London mural by famed street artist Banksy. The mural was on a private building and it was painted over by, er, mistake. The Council had sent letters requesting to "clean" the building but they had gone to the wrong address. From the BBC News:
Property owner Sofie Attrill gave consent for the mural to be painted on the building so it could be photographed for the launch of Blur's 2003 single Crazy Beat.Blur Banksy is ruined by mistake (Thanks, Antinous!)
Since then it has attracted tourists from all over the world and become a local landmark...
Hackney Council was initially unrepentant.
Cllr Alan Laing said: "The council's position is not to make a judgement call on whether graffiti is art."
But he later added: "Due to a problem at the land registry unfortunately our letters stating our intention to clean this building didn't reach the owner.
"As soon as we realised this, work stopped. We are now speaking with her about how to resolve the issue."